diff --git a/main/admin/access_url_add_courses_to_url.php b/main/admin/access_url_add_courses_to_url.php
index c8ab1f50e7..7a4825913d 100755
--- a/main/admin/access_url_add_courses_to_url.php
+++ b/main/admin/access_url_add_courses_to_url.php
@@ -31,7 +31,7 @@ $tool_name = get_lang('AddCoursesToURL');
 $interbreadcrumb[] = ['url' => 'index.php', 'name' => get_lang('PlatformAdmin')];
 $interbreadcrumb[] = ['url' => 'access_urls.php', 'name' => get_lang('MultipleAccessURLs')];
 
-Display :: display_header($tool_name);
+Display::display_header($tool_name);
 
 echo '<div class="actions">';
 echo Display::url(
@@ -91,8 +91,8 @@ unset($result);
      <select name="first_letter_course" onchange="javascript:document.formulaire.form_sent.value='2'; document.formulaire.submit();">
       <option value="">--</option>
     <?php
-    echo Display:: get_alphabet_options($first_letter_course);
-    echo Display:: get_numeric_options(0, 9, $first_letter_course);
+    echo Display::get_alphabet_options($first_letter_course);
+    echo Display::get_numeric_options(0, 9, $first_letter_course);
     ?>
      </select>
     </td>
@@ -136,4 +136,4 @@ unset($result);
 </form>
 <?php
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/access_url_add_usergroup_to_url.php b/main/admin/access_url_add_usergroup_to_url.php
index 3209289160..61e5c6b8ae 100755
--- a/main/admin/access_url_add_usergroup_to_url.php
+++ b/main/admin/access_url_add_usergroup_to_url.php
@@ -122,4 +122,4 @@ $db_urls = Database::store_result($result);
 </form>
 <?php
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/access_url_add_users_to_url.php b/main/admin/access_url_add_users_to_url.php
index 45bf76c714..442ec3a080 100755
--- a/main/admin/access_url_add_users_to_url.php
+++ b/main/admin/access_url_add_users_to_url.php
@@ -29,7 +29,7 @@ $tool_name = get_lang('AddUsersToURL');
 $interbreadcrumb[] = ['url' => 'index.php', 'name' => get_lang('PlatformAdmin')];
 $interbreadcrumb[] = ['url' => 'access_urls.php', 'name' => get_lang('MultipleAccessURLs')];
 
-Display :: display_header($tool_name);
+Display::display_header($tool_name);
 
 echo '<div class="actions">';
 echo Display::url(
@@ -102,7 +102,7 @@ unset($result);
      <select name="first_letter_user" onchange="javascript:document.formulaire.form_sent.value='2'; document.formulaire.submit();">
       <option value="">--</option>
       <?php
-        echo Display :: get_alphabet_options($first_letter_user);
+        echo Display::get_alphabet_options($first_letter_user);
         ?>
      </select>
     </td>
@@ -150,4 +150,4 @@ unset($result);
 </form>
 <?php
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/access_url_check_user_session.php b/main/admin/access_url_check_user_session.php
index 074a1d1a8e..9064c9c9a6 100755
--- a/main/admin/access_url_check_user_session.php
+++ b/main/admin/access_url_check_user_session.php
@@ -111,4 +111,4 @@ foreach ($session_list as $session_item) {
 }
 echo $html;
 // footer
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/access_url_edit.php b/main/admin/access_url_edit.php
index 1838275be7..c5995476cb 100755
--- a/main/admin/access_url_edit.php
+++ b/main/admin/access_url_edit.php
@@ -146,7 +146,7 @@ $tool_name = get_lang('AddUrl');
 $interbreadcrumb[] = ['url' => 'index.php', 'name' => get_lang('PlatformAdmin')];
 $interbreadcrumb[] = ['url' => 'access_urls.php', 'name' => get_lang('MultipleAccessURLs')];
 
-Display :: display_header($tool_name);
+Display::display_header($tool_name);
 
 // URL Images
 $form->addElement('file', 'url_image_1', 'URL Image 1 (PNG)');
diff --git a/main/admin/access_urls.php b/main/admin/access_urls.php
index dfe0cd52ec..fc4f67aa6a 100755
--- a/main/admin/access_urls.php
+++ b/main/admin/access_urls.php
@@ -21,7 +21,7 @@ if (!api_get_multiple_access_url()) {
 
 $interbreadcrumb[] = ['url' => 'index.php', 'name' => get_lang('PlatformAdmin')];
 $tool_name = get_lang('MultipleAccessURLs');
-Display :: display_header($tool_name);
+Display::display_header($tool_name);
 
 $my_user_url_list = api_get_access_url_from_user(api_get_user_id());
 $current_access_url_id = api_get_current_access_url_id();
@@ -184,4 +184,4 @@ $table->set_header(3, get_lang('CreatedAt'));
 $table->set_header(4, get_lang('Modify'), false);
 $table->display();
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/add_courses_to_usergroup.php b/main/admin/add_courses_to_usergroup.php
index 22f2204550..aad69196a0 100755
--- a/main/admin/add_courses_to_usergroup.php
+++ b/main/admin/add_courses_to_usergroup.php
@@ -217,7 +217,7 @@ if (!empty($errorMsg)) {
     <select name="firstLetterUser" onchange = "xajax_search(this.value,'multiple')" >
     <option value = "%">--</option>
     <?php
-    echo Display :: get_alphabet_options(); ?>
+    echo Display::get_alphabet_options(); ?>
     </select>
 </td>
 <td align="center">&nbsp;</td>
diff --git a/main/admin/add_sessions_to_promotion.php b/main/admin/add_sessions_to_promotion.php
index 0f2aed3054..8347e30831 100755
--- a/main/admin/add_sessions_to_promotion.php
+++ b/main/admin/add_sessions_to_promotion.php
@@ -178,7 +178,7 @@ if (!empty($errorMsg)) {
      <select name="firstLetterUser" onchange = "xajax_search_sessions(this.value,'multiple')" >
       <option value = "%">--</option>
       <?php
-        echo Display :: get_alphabet_options(); ?>
+        echo Display::get_alphabet_options(); ?>
      </select>
 </td>
 <td align="center">&nbsp;</td>
diff --git a/main/admin/add_sessions_to_usergroup.php b/main/admin/add_sessions_to_usergroup.php
index 7f8c35ccd6..93eaf5b591 100755
--- a/main/admin/add_sessions_to_usergroup.php
+++ b/main/admin/add_sessions_to_usergroup.php
@@ -199,7 +199,7 @@ if (!empty($errorMsg)) {
      <select name="firstLetterUser" onchange = "xajax_search_usergroup_sessions(this.value,'multiple')" >
       <option value = "%">--</option>
       <?php
-        echo Display :: get_alphabet_options(); ?>
+        echo Display::get_alphabet_options(); ?>
      </select>
 <?php echo '<br />'; ?>
 </td>
diff --git a/main/admin/cli.php b/main/admin/cli.php
index d176d281f0..1072f24a05 100755
--- a/main/admin/cli.php
+++ b/main/admin/cli.php
@@ -21,7 +21,7 @@ $tool_name = get_lang('CommandLineInterpreter');
 // setting breadcrumbs
 $interbreadcrumb[] = ['url' => 'index.php', 'name' => get_lang('PlatformAdmin')];
 // including the header file (which includes the banner itself)
-Display :: display_header($tool_name);
+Display::display_header($tool_name);
 switch ($_GET["cmd"]) {
     case "clear_stapi":
         echo "Are you sure you are willing to erase all storage api data (no backup)? <a href='cli.php?cmd=clear_stapi_confirm' >Yes</a>";
@@ -36,4 +36,4 @@ switch ($_GET["cmd"]) {
         break;
 }
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/configure_inscription.php b/main/admin/configure_inscription.php
index f3d85fe4ed..6fa8d9e94a 100755
--- a/main/admin/configure_inscription.php
+++ b/main/admin/configure_inscription.php
@@ -24,7 +24,7 @@ if (api_get_setting('allow_terms_conditions') === 'true') {
                 $term_preview = LegalManager::get_last_condition($language);
             }
             $tool_name = get_lang('TermsAndConditions');
-            Display:: display_header('');
+            Display::display_header('');
             echo '<div class="actions-title">';
             echo $tool_name;
             echo '</div>';
@@ -33,7 +33,7 @@ if (api_get_setting('allow_terms_conditions') === 'true') {
             } else {
                 echo get_lang('ComingSoon');
             }
-            Display:: display_footer();
+            Display::display_footer();
             exit;
         }
     }
@@ -151,7 +151,7 @@ if (!empty($action)) {
     }
 }
 
-Display:: display_header($tool_name);
+Display::display_header($tool_name);
 
 echo Display::page_header($tool_name);
 
@@ -464,4 +464,4 @@ switch ($action) {
         break;
 }
 
-Display:: display_footer();
+Display::display_footer();
diff --git a/main/admin/course_export.php b/main/admin/course_export.php
index 906dbe8298..3937e00708 100755
--- a/main/admin/course_export.php
+++ b/main/admin/course_export.php
@@ -187,4 +187,4 @@ $form->setDefaults(['select_type' => '1', 'file_type' => 'csv', 'include_users'
 $form->addButtonExport(get_lang('ExportCourses'));
 $form->display();
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/course_information.php b/main/admin/course_information.php
index 4deab8d183..361e554d3d 100755
--- a/main/admin/course_information.php
+++ b/main/admin/course_information.php
@@ -152,7 +152,7 @@ if (Database::num_rows($res) > 0) {
             $user[] = $obj->lastname;
             $user[] = $obj->firstname;
         }
-        $user[] = Display:: encrypted_mailto_link($obj->email, $obj->email);
+        $user[] = Display::encrypted_mailto_link($obj->email, $obj->email);
         $user[] = $obj->course_status == 5 ? get_lang('Student') : get_lang('Teacher');
         $user[] = '<a href="user_information.php?user_id='.$obj->user_id.'">'.
             Display::return_icon('info2.png', get_lang('UserInfo')).'</a>';
diff --git a/main/admin/course_request_accepted.php b/main/admin/course_request_accepted.php
index 26416bcaf0..a5f59a0d4f 100755
--- a/main/admin/course_request_accepted.php
+++ b/main/admin/course_request_accepted.php
@@ -107,10 +107,10 @@ function get_request_data($from, $number_of_items, $column, $direction)
     }
     $sql .= " ORDER BY col$column $direction ";
     $sql .= " LIMIT $from,$number_of_items";
-    $res = Database :: query($sql);
+    $res = Database::query($sql);
 
     $course_requests = [];
-    while ($course_request = Database :: fetch_row($res)) {
+    while ($course_request = Database::fetch_row($res)) {
         $course_request[5] = api_get_local_time($course_request[5]);
         $course_requests[] = $course_request;
     }
@@ -153,10 +153,10 @@ if (!empty($message)) {
     }
 }
 
-Display :: display_header($tool_name);
+Display::display_header($tool_name);
 
 if (!$course_validation_feature) {
-    Display :: display_footer();
+    Display::display_footer();
     exit;
 }
 
@@ -193,4 +193,4 @@ $table->display();
 
 /* FOOTER */
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/course_request_edit.php b/main/admin/course_request_edit.php
index ad5f31ab85..ce528ad341 100755
--- a/main/admin/course_request_edit.php
+++ b/main/admin/course_request_edit.php
@@ -328,7 +328,7 @@ function get_caller_name($caller_id)
 $interbreadcrumb[] = ['url' => 'index.php', 'name' => get_lang('PlatformAdmin')];
 $interbreadcrumb[] = ['url' => 'course_list.php', 'name' => get_lang('CourseList')];
 
-Display :: display_header($tool_name);
+Display::display_header($tool_name);
 
 if (!$course_validation_feature) {
     // Disabled course validation feature - show nothing after the error message.
diff --git a/main/admin/course_request_rejected.php b/main/admin/course_request_rejected.php
index 9c51db9580..fa543e6887 100755
--- a/main/admin/course_request_rejected.php
+++ b/main/admin/course_request_rejected.php
@@ -138,10 +138,10 @@ function get_request_data($from, $number_of_items, $column, $direction)
     }
     $sql .= " ORDER BY col$column $direction ";
     $sql .= " LIMIT $from,$number_of_items";
-    $res = Database :: query($sql);
+    $res = Database::query($sql);
 
     $course_requests = [];
-    while ($course_request = Database :: fetch_row($res)) {
+    while ($course_request = Database::fetch_row($res)) {
         $course_request[5] = api_get_local_time($course_request[5]);
         $course_requests[] = $course_request;
     }
@@ -210,7 +210,7 @@ if (!empty($message)) {
 Display::display_header($tool_name);
 
 if (!$course_validation_feature) {
-    Display :: display_footer();
+    Display::display_footer();
     exit;
 }
 
diff --git a/main/admin/course_request_review.php b/main/admin/course_request_review.php
index eb58cb3c71..e563535120 100755
--- a/main/admin/course_request_review.php
+++ b/main/admin/course_request_review.php
@@ -240,7 +240,7 @@ if (!empty($message)) {
 Display::display_header($tool_name);
 
 if (!$course_validation_feature) {
-    Display :: display_footer();
+    Display::display_footer();
     exit;
 }
 
diff --git a/main/admin/course_user_import.php b/main/admin/course_user_import.php
index 4b216a7550..ff621693b4 100755
--- a/main/admin/course_user_import.php
+++ b/main/admin/course_user_import.php
@@ -197,7 +197,7 @@ if ($form->validate()) {
 }
 
 // Displaying the header.
-Display :: display_header($tool_name);
+Display::display_header($tool_name);
 
 if (count($errors) != 0) {
     $error_message = '<ul>';
@@ -228,4 +228,4 @@ adam;course01;<?php echo STUDENT; ?>
     </blockquote>
 <?php
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/dashboard_add_courses_to_user.php b/main/admin/dashboard_add_courses_to_user.php
index 6bb3b7ca5b..f7e524fa39 100755
--- a/main/admin/dashboard_add_courses_to_user.php
+++ b/main/admin/dashboard_add_courses_to_user.php
@@ -88,7 +88,7 @@ function search_courses($needle, $type)
         $rs = Database::query($sql);
 
         $return .= '<select id="origin" name="NoAssignedCoursesList[]" multiple="multiple" size="20" >';
-        while ($course = Database :: fetch_array($rs)) {
+        while ($course = Database::fetch_array($rs)) {
             $return .= '<option value="'.$course['code'].'" title="'.htmlspecialchars($course['title'], ENT_QUOTES).'">'.$course['title'].' ('.$course['code'].')</option>';
         }
         $return .= '</select>';
@@ -247,7 +247,7 @@ if (!empty($msg)) {
         <p><?php echo get_lang('FirstLetterCourse'); ?> :</p>
         <select name="firstLetterCourse" class="selectpicker form-control" onchange = "xajax_search_courses(this.value,'multiple')">
             <option value="%">--</option>
-            <?php echo Display :: get_alphabet_options($firstLetter); ?>
+            <?php echo Display::get_alphabet_options($firstLetter); ?>
         </select>
         <?php
     } ?>
diff --git a/main/admin/dashboard_add_sessions_to_user.php b/main/admin/dashboard_add_sessions_to_user.php
index e06baa1f6c..51867638e0 100755
--- a/main/admin/dashboard_add_sessions_to_user.php
+++ b/main/admin/dashboard_add_sessions_to_user.php
@@ -83,7 +83,7 @@ function search_sessions($needle, $type)
         }
         $rs = Database::query($sql);
         $return .= '<select class="form-control" id="origin" name="NoAssignedSessionsList[]" multiple="multiple" size="20">';
-        while ($session = Database :: fetch_array($rs)) {
+        while ($session = Database::fetch_array($rs)) {
             $return .= '<option value="'.$session['id'].'" title="'.htmlspecialchars($session['name'], ENT_QUOTES).'">'.$session['name'].'</option>';
         }
         $return .= '</select>';
@@ -243,7 +243,7 @@ $result = Database::query($sql);
                 <p><?php echo get_lang('FirstLetterSession'); ?> :</p>
                 <select class="selectpicker form-control" name="firstLetterSession" onchange = "xajax_search_sessions(this.value, 'multiple')">
                     <option value="%">--</option>
-                        <?php echo Display :: get_alphabet_options($firstLetterSession); ?>
+                        <?php echo Display::get_alphabet_options($firstLetterSession); ?>
                 </select>
                 <?php
                     } ?>
diff --git a/main/admin/dashboard_add_users_to_user.php b/main/admin/dashboard_add_users_to_user.php
index a46c5b0727..1b90666cb1 100755
--- a/main/admin/dashboard_add_users_to_user.php
+++ b/main/admin/dashboard_add_users_to_user.php
@@ -151,7 +151,7 @@ function search_users($needle, $type = 'multiple')
 
             $rs = Database::query($sql);
             $i = 0;
-            while ($user = Database :: fetch_array($rs)) {
+            while ($user = Database::fetch_array($rs)) {
                 $i++;
                 if ($i <= 10) {
                     $person_name = api_get_person_name($user['firstname'], $user['lastname']);
@@ -167,7 +167,7 @@ function search_users($needle, $type = 'multiple')
             );
         } else {
             $return .= '<select id="origin" class="form-control" name="NoAssignedUsersList[]" multiple="multiple" size="15" ">';
-            while ($user = Database :: fetch_array($rs)) {
+            while ($user = Database::fetch_array($rs)) {
                 $person_name = api_get_person_name($user['firstname'], $user['lastname']);
                 $return .= '<option value="'.$user['user_id'].'" title="'.htmlspecialchars($person_name, ENT_QUOTES).'">'.$person_name.' ('.$user['username'].')</option>';
             }
diff --git a/main/admin/event_type.php b/main/admin/event_type.php
index 99704f4543..6e718e0a3b 100755
--- a/main/admin/event_type.php
+++ b/main/admin/event_type.php
@@ -406,4 +406,4 @@ echo Display::actions($action_array);
 
 </form>
 <?php
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/export_certificates.php b/main/admin/export_certificates.php
index f872a64870..f25e44ce0c 100644
--- a/main/admin/export_certificates.php
+++ b/main/admin/export_certificates.php
@@ -30,7 +30,7 @@ if ($form->validate()) {
         $courseInfo = api_get_course_info_by_id($courseId);
         $courseCode = $courseInfo['code'];
 
-        $cats = Category:: load(
+        $cats = Category::load(
             null,
             null,
             $courseCode,
@@ -60,4 +60,4 @@ if ($form->validate()) {
     }
 }
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/index.php b/main/admin/index.php
index b92151d23c..b12572b93b 100644
--- a/main/admin/index.php
+++ b/main/admin/index.php
@@ -46,7 +46,7 @@ if (api_is_platform_admin()) {
     /* ACTION HANDLING */
     if (!empty($_POST['Register'])) {
         api_register_campus(!$_POST['donotlistcampus']);
-        $message = Display :: return_message(get_lang('VersionCheckEnabled'), 'confirmation');
+        $message = Display::return_message(get_lang('VersionCheckEnabled'), 'confirmation');
         Display::addFlash($message);
     }
     $keyword_url = Security::remove_XSS((empty($_GET['keyword']) ? '' : $_GET['keyword']));
diff --git a/main/admin/languages.php b/main/admin/languages.php
index c1d11bcd9f..d666fe4465 100755
--- a/main/admin/languages.php
+++ b/main/admin/languages.php
@@ -344,4 +344,4 @@ $table->set_form_actions($form_actions);
 echo '<div id="id_content_message">&nbsp;</div>';
 $table->display();
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/legal_list.php b/main/admin/legal_list.php
index 8a37563bbf..b55c65f9e7 100755
--- a/main/admin/legal_list.php
+++ b/main/admin/legal_list.php
@@ -59,4 +59,4 @@ function count_mask()
     return LegalManager::count();
 }
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/skills_import.php b/main/admin/skills_import.php
index af8bfaa0b9..eb8cb1d56b 100755
--- a/main/admin/skills_import.php
+++ b/main/admin/skills_import.php
@@ -174,7 +174,7 @@ if (!empty($_POST['formSent']) && $_FILES['import_file']['size'] !== 0) {
 
 $interbreadcrumb[] = ["url" => 'skill_list.php', "name" => get_lang('ManageSkills')];
 
-Display :: display_header($tool_name);
+Display::display_header($tool_name);
 
 if (!empty($error_message)) {
     echo Display::return_message($error_message, 'error');
@@ -214,4 +214,4 @@ $form->display();
     <b>2</b>;<b>1</b>;<b>Chamilo Expert</b>;Chamilo is an open source LMS;<br />
 </pre>
 <?php
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/special_exports.php b/main/admin/special_exports.php
index 3da18bc54a..f0da41c8ef 100755
--- a/main/admin/special_exports.php
+++ b/main/admin/special_exports.php
@@ -133,7 +133,7 @@ if ($export && $name) {
             form_special_export();
         } else {
             echo Display::return_message(get_lang('ToExportSpecialSelect'), 'normal');
-            CourseSelectForm :: display_form_session_export($course);
+            CourseSelectForm::display_form_session_export($course);
         }
     } else {
         form_special_export();
diff --git a/main/admin/sub_language.php b/main/admin/sub_language.php
index cb5985d24d..8bf51d59cc 100755
--- a/main/admin/sub_language.php
+++ b/main/admin/sub_language.php
@@ -93,7 +93,7 @@ if (!is_dir($path_folder) || strlen($all_data_of_language['dokeos_folder']) == 0
     api_not_allowed(true);
 }
 
-Display :: display_header($language_name);
+Display::display_header($language_name);
 
 echo '<div class="actions-message" >';
 echo $intro;
@@ -384,4 +384,4 @@ $table->set_header(5, get_lang('Action'), false);
 $table->setHideColumn(0);
 $table->display();
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/sub_language_add.php b/main/admin/sub_language_add.php
index ed0b252f0a..bad6b25b13 100755
--- a/main/admin/sub_language_add.php
+++ b/main/admin/sub_language_add.php
@@ -276,7 +276,7 @@ if (isset($_POST['SubmitAddNewLanguage'])) {
     }
 }
 
-Display:: display_header($language_name);
+Display::display_header($language_name);
 
 echo $msg;
 
@@ -335,4 +335,4 @@ if (isset($_GET['action']) && $_GET['action'] == 'definenewsublanguage') {
 /**
  * Footer.
  */
-Display:: display_footer();
+Display::display_footer();
diff --git a/main/admin/subscribe_user2course.php b/main/admin/subscribe_user2course.php
index 81de085ed5..ecb57e269b 100755
--- a/main/admin/subscribe_user2course.php
+++ b/main/admin/subscribe_user2course.php
@@ -38,7 +38,7 @@ function validate_filter() {
 </script>';
 
 // displaying the header
-Display :: display_header($tool_name);
+Display::display_header($tool_name);
 
 $link_add_group = '<a href="usergroups.php">'.
     Display::return_icon('multiple.gif', get_lang('RegistrationByUsersGroups')).get_lang('RegistrationByUsersGroups').'</a>';
@@ -295,7 +295,7 @@ if (is_array($extra_field_list)) {
         aria-label="<?php echo get_lang('FirstLetterUser'); ?>">
       <option value="">--</option>
       <?php
-        echo Display :: get_alphabet_options($first_letter_user);
+        echo Display::get_alphabet_options($first_letter_user);
       ?>
      </select>
     </td>
@@ -309,7 +309,7 @@ if (is_array($extra_field_list)) {
         aria-label="<?php echo get_lang('FirstLetterCourse'); ?>">
       <option value="">--</option>
       <?php
-      echo Display :: get_alphabet_options($first_letter_course);
+      echo Display::get_alphabet_options($first_letter_course);
       ?>
      </select>
     </td>
@@ -357,4 +357,4 @@ if (is_array($extra_field_list)) {
 </form>
 <?php
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/system_announcements.php b/main/admin/system_announcements.php
index 33c284af93..8ece2c5203 100755
--- a/main/admin/system_announcements.php
+++ b/main/admin/system_announcements.php
@@ -318,7 +318,7 @@ if ($action_todo) {
 }
 
 if ($show_announcement_list) {
-    $announcements = SystemAnnouncementManager :: get_all_announcements();
+    $announcements = SystemAnnouncementManager::get_all_announcements();
     $announcement_data = [];
     foreach ($announcements as $index => $announcement) {
         $row = [];
@@ -364,4 +364,4 @@ if ($show_announcement_list) {
     $table->display();
 }
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/user_export.php b/main/admin/user_export.php
index ef143db499..85ceca43d5 100755
--- a/main/admin/user_export.php
+++ b/main/admin/user_export.php
@@ -183,7 +183,7 @@ if ($form->validate()) {
             }
         }
 
-        $studentData = UserManager:: get_extra_user_data(
+        $studentData = UserManager::get_extra_user_data(
             $user['UserId'],
             true,
             false
@@ -214,6 +214,6 @@ if ($form->validate()) {
     }
 }
 
-Display :: display_header($tool_name);
+Display::display_header($tool_name);
 $form->display();
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/admin/user_information.php b/main/admin/user_information.php
index 0ba941d076..d741b7dd59 100755
--- a/main/admin/user_information.php
+++ b/main/admin/user_information.php
@@ -346,7 +346,7 @@ if (count($sessions) > 0) {
             }
 
             $timeSpent = api_time_to_hms(
-                Tracking :: get_time_spent_on_the_course(
+                Tracking::get_time_spent_on_the_course(
                     $userId,
                     $courseInfo['real_id'],
                     $id_session
diff --git a/main/auth/key/key_auth.class.php b/main/auth/key/key_auth.class.php
index 203d81a8f4..92537a2efa 100755
--- a/main/auth/key/key_auth.class.php
+++ b/main/auth/key/key_auth.class.php
@@ -41,7 +41,7 @@ use ChamiloSession as Session;
  */
 class KeyAuth
 {
-    const PARAM_ACCESS_TOKEN = 'access_token';
+    public const PARAM_ACCESS_TOKEN = 'access_token';
 
     protected static $services = [];
 
diff --git a/main/auth/profile.php b/main/auth/profile.php
index 535d1ee4f8..393ee9eb4d 100755
--- a/main/auth/profile.php
+++ b/main/auth/profile.php
@@ -436,7 +436,7 @@ if ($form->validate()) {
             $password = $user_data['password1'];
         } else {
             Display::addFlash(
-                Display:: return_message(
+                Display::return_message(
                     get_lang('CurrentPasswordEmptyOrIncorrect'),
                     'warning',
                     false
@@ -466,7 +466,7 @@ if ($form->validate()) {
 
             if (!check_user_email($user_data['email']) && empty($user_data['password0'])) {
                 Display::addFlash(
-                    Display:: return_message(
+                    Display::return_message(
                         get_lang('ToChangeYourEmailMustTypeYourPassword'),
                         'error',
                         false
@@ -489,7 +489,7 @@ if ($form->validate()) {
             $user_data['picture_uri'] = $new_picture;
 
             Display::addFlash(
-                Display:: return_message(
+                Display::return_message(
                     get_lang('PictureUploaded'),
                     'normal',
                     false
@@ -517,7 +517,7 @@ if ($form->validate()) {
         }
         $form->removeElement('productions_list');
         Display::addFlash(
-            Display:: return_message(get_lang('FileDeleted'), 'normal', false)
+            Display::return_message(get_lang('FileDeleted'), 'normal', false)
         );
     }
 
@@ -530,7 +530,7 @@ if ($form->validate()) {
             $filtered_extension = true;
         } else {
             Display::addFlash(
-                Display:: return_message(
+                Display::return_message(
                     get_lang('ProductionUploaded'),
                     'normal',
                     false
@@ -650,12 +650,12 @@ if ($form->validate()) {
 
     if ($passwordWasChecked == false) {
         Display::addFlash(
-            Display:: return_message(get_lang('ProfileReg'), 'normal', false)
+            Display::return_message(get_lang('ProfileReg'), 'normal', false)
         );
     } else {
         if ($validPassword) {
             Display::addFlash(
-                Display:: return_message(get_lang('ProfileReg'), 'normal', false)
+                Display::return_message(get_lang('ProfileReg'), 'normal', false)
             );
         }
     }
diff --git a/main/common_cartridge/export/src/CcForum.php b/main/common_cartridge/export/src/CcForum.php
index 22dd89704a..a4e189457b 100644
--- a/main/common_cartridge/export/src/CcForum.php
+++ b/main/common_cartridge/export/src/CcForum.php
@@ -3,7 +3,7 @@
 
 class CcForum extends CcGeneralFile
 {
-    const DEAFULTNAME = 'discussion.xml';
+    public const DEAFULTNAME = 'discussion.xml';
     protected $rootns = 'dt';
     protected $rootname = 'topic';
     protected $ccnamespaces = ['dt' => 'http://www.imsglobal.org/xsd/imsccv1p3/imsdt_v1p3',
diff --git a/main/common_cartridge/export/src/CcVersion13.php b/main/common_cartridge/export/src/CcVersion13.php
index 6fdd0b99c0..933b17cef6 100644
--- a/main/common_cartridge/export/src/CcVersion13.php
+++ b/main/common_cartridge/export/src/CcVersion13.php
@@ -3,13 +3,13 @@
 
 class CcVersion13 extends CcVersion1
 {
-    const WEBCONTENT = 'webcontent';
-    const QUESTIONBANK = 'imsqti_xmlv1p3/imscc_xmlv1p3/question-bank';
-    const ASSESSMENT = 'imsqti_xmlv1p3/imscc_xmlv1p3/assessment';
-    const ASSOCIATEDCONTENT = 'associatedcontent/imscc_xmlv1p3/learning-application-resource';
-    const DISCUSSIONTOPIC = 'imsdt_xmlv1p3';
-    const WEBLINK = 'imswl_xmlv1p3';
-    const BASICLTI = 'imsbasiclti_xmlv1p3';
+    public const WEBCONTENT = 'webcontent';
+    public const QUESTIONBANK = 'imsqti_xmlv1p3/imscc_xmlv1p3/question-bank';
+    public const ASSESSMENT = 'imsqti_xmlv1p3/imscc_xmlv1p3/assessment';
+    public const ASSOCIATEDCONTENT = 'associatedcontent/imscc_xmlv1p3/learning-application-resource';
+    public const DISCUSSIONTOPIC = 'imsdt_xmlv1p3';
+    public const WEBLINK = 'imswl_xmlv1p3';
+    public const BASICLTI = 'imsbasiclti_xmlv1p3';
 
     public static $checker = [self::WEBCONTENT,
                                    self::ASSESSMENT,
diff --git a/main/common_cartridge/export/src/CcWebLink.php b/main/common_cartridge/export/src/CcWebLink.php
index 489b866074..25fbe84b1d 100644
--- a/main/common_cartridge/export/src/CcWebLink.php
+++ b/main/common_cartridge/export/src/CcWebLink.php
@@ -3,7 +3,7 @@
 
 class CcWebLink extends CcGeneralFile
 {
-    const DEAFULTNAME = 'weblink.xml';
+    public const DEAFULTNAME = 'weblink.xml';
 
     protected $rootns = 'wl';
     protected $rootname = 'webLink';
diff --git a/main/common_cartridge/export/src/base/CcVersion1.php b/main/common_cartridge/export/src/base/CcVersion1.php
index c273a57bcb..7d7225bd2c 100644
--- a/main/common_cartridge/export/src/base/CcVersion1.php
+++ b/main/common_cartridge/export/src/base/CcVersion1.php
@@ -6,12 +6,12 @@
  */
 class CcVersion1 extends CcVersionBase
 {
-    const WEBCONTENT = 'webcontent';
-    const QUESTIONBANK = 'imsqti_xmlv1p2/imscc_xmlv1p0/question-bank';
-    const ASSESSMENT = 'imsqti_xmlv1p2/imscc_xmlv1p0/assessment';
-    const ASSOCIATEDCONTENT = 'associatedcontent/imscc_xmlv1p0/learning-application-resource';
-    const DISCUSSIONTOPIC = 'imsdt_xmlv1p0';
-    const WEBLINK = 'imswl_xmlv1p0';
+    public const WEBCONTENT = 'webcontent';
+    public const QUESTIONBANK = 'imsqti_xmlv1p2/imscc_xmlv1p0/question-bank';
+    public const ASSESSMENT = 'imsqti_xmlv1p2/imscc_xmlv1p0/assessment';
+    public const ASSOCIATEDCONTENT = 'associatedcontent/imscc_xmlv1p0/learning-application-resource';
+    public const DISCUSSIONTOPIC = 'imsdt_xmlv1p0';
+    public const WEBLINK = 'imswl_xmlv1p0';
 
     public static $checker = [self::WEBCONTENT,
                                    self::ASSESSMENT,
diff --git a/main/common_cartridge/export/src/lib/assesment/Assesment1ResourceFile.php b/main/common_cartridge/export/src/lib/assesment/Assesment1ResourceFile.php
index ea1ac75405..baa22db63f 100644
--- a/main/common_cartridge/export/src/lib/assesment/Assesment1ResourceFile.php
+++ b/main/common_cartridge/export/src/lib/assesment/Assesment1ResourceFile.php
@@ -3,7 +3,7 @@
 
 class Assesment1ResourceFile extends CcGeneralFile
 {
-    const DEAFULTNAME = 'assesment.xml';
+    public const DEAFULTNAME = 'assesment.xml';
 
     protected $rootns = 'xmlns';
     protected $rootname = CcQtiTags::QUESTESTINTEROP;
diff --git a/main/common_cartridge/export/src/lib/assesment/CcQtiMetadata.php b/main/common_cartridge/export/src/lib/assesment/CcQtiMetadata.php
index 3930634a7d..4d554764af 100644
--- a/main/common_cartridge/export/src/lib/assesment/CcQtiMetadata.php
+++ b/main/common_cartridge/export/src/lib/assesment/CcQtiMetadata.php
@@ -4,19 +4,19 @@
 abstract class CcQtiMetadata
 {
     // Assessment.
-    const QMD_ASSESSMENTTYPE = 'qmd_assessmenttype';
-    const QMD_SCORETYPE = 'qmd_scoretype';
-    const QMD_FEEDBACKPERMITTED = 'qmd_feedbackpermitted';
-    const QMD_HINTSPERMITTED = 'qmd_hintspermitted';
-    const QMD_SOLUTIONSPERMITTED = 'qmd_solutionspermitted';
-    const QMD_TIMELIMIT = 'qmd_timelimit';
-    const CC_ALLOW_LATE_SUBMISSION = 'cc_allow_late_submission';
-    const CC_MAXATTEMPTS = 'cc_maxattempts';
-    const CC_PROFILE = 'cc_profile';
+    public const QMD_ASSESSMENTTYPE = 'qmd_assessmenttype';
+    public const QMD_SCORETYPE = 'qmd_scoretype';
+    public const QMD_FEEDBACKPERMITTED = 'qmd_feedbackpermitted';
+    public const QMD_HINTSPERMITTED = 'qmd_hintspermitted';
+    public const QMD_SOLUTIONSPERMITTED = 'qmd_solutionspermitted';
+    public const QMD_TIMELIMIT = 'qmd_timelimit';
+    public const CC_ALLOW_LATE_SUBMISSION = 'cc_allow_late_submission';
+    public const CC_MAXATTEMPTS = 'cc_maxattempts';
+    public const CC_PROFILE = 'cc_profile';
 
     // Items.
-    const CC_WEIGHTING = 'cc_weighting';
-    const QMD_SCORINGPERMITTED = 'qmd_scoringpermitted';
-    const QMD_COMPUTERSCORED = 'qmd_computerscored';
-    const CC_QUESTION_CATEGORY = 'cc_question_category';
+    public const CC_WEIGHTING = 'cc_weighting';
+    public const QMD_SCORINGPERMITTED = 'qmd_scoringpermitted';
+    public const QMD_COMPUTERSCORED = 'qmd_computerscored';
+    public const CC_QUESTION_CATEGORY = 'cc_question_category';
 }
diff --git a/main/common_cartridge/export/src/lib/assesment/CcQtiProfiletype.php b/main/common_cartridge/export/src/lib/assesment/CcQtiProfiletype.php
index 22664e5727..8f88a09f9d 100644
--- a/main/common_cartridge/export/src/lib/assesment/CcQtiProfiletype.php
+++ b/main/common_cartridge/export/src/lib/assesment/CcQtiProfiletype.php
@@ -3,12 +3,12 @@
 
 abstract class CcQtiProfiletype
 {
-    const MULTIPLE_CHOICE = 'cc.multiple_choice.v0p1';
-    const MULTIPLE_RESPONSE = 'cc.multiple_response.v0p1';
-    const TRUE_FALSE = 'cc.true_false.v0p1';
-    const FIELD_ENTRY = 'cc.fib.v0p1';
-    const PATTERN_MATCH = 'cc.pattern_match.v0p1';
-    const ESSAY = 'cc.essay.v0p1';
+    public const MULTIPLE_CHOICE = 'cc.multiple_choice.v0p1';
+    public const MULTIPLE_RESPONSE = 'cc.multiple_response.v0p1';
+    public const TRUE_FALSE = 'cc.true_false.v0p1';
+    public const FIELD_ENTRY = 'cc.fib.v0p1';
+    public const PATTERN_MATCH = 'cc.pattern_match.v0p1';
+    public const ESSAY = 'cc.essay.v0p1';
 
     /**
      * validates a profile value.
diff --git a/main/common_cartridge/export/src/lib/assesment/CcQtiTags.php b/main/common_cartridge/export/src/lib/assesment/CcQtiTags.php
index 599ec808ef..e044d7c01e 100644
--- a/main/common_cartridge/export/src/lib/assesment/CcQtiTags.php
+++ b/main/common_cartridge/export/src/lib/assesment/CcQtiTags.php
@@ -3,86 +3,86 @@
 
 abstract class CcQtiTags
 {
-    const QUESTESTINTEROP = 'questestinterop';
-    const ASSESSMENT = 'assessment';
-    const QTIMETADATA = 'qtimetadata';
-    const QTIMETADATAFIELD = 'qtimetadatafield';
-    const FIELDLABEL = 'fieldlabel';
-    const FIELDENTRY = 'fieldentry';
-    const SECTION = 'section';
-    const IDENT = 'ident';
-    const ITEM = 'item';
-    const TITLE = 'title';
-    const ITEMMETADATA = 'itemmetadata';
-    const PRESENTATION = 'presentation';
-    const MATERIAL = 'material';
-    const MATTEXT = 'mattext';
-    const MATREF = 'matref';
-    const MATBREAK = 'matbreak';
-    const TEXTTYPE = 'texttype';
-    const RESPONSE_LID = 'response_lid';
-    const RENDER_CHOICE = 'render_choice';
-    const RESPONSE_LABEL = 'response_label';
-    const RESPROCESSING = 'resprocessing';
-    const OUTCOMES = 'outcomes';
-    const DECVAR = 'decvar';
-    const RESPCONDITION = 'respcondition';
-    const CONDITIONVAR = 'conditionvar';
-    const OTHER = 'other';
-    const DISPLAYFEEDBACK = 'displayfeedback';
-    const MAXVALUE = 'maxvalue';
-    const MINVALUE = 'minvalue';
-    const VARNAME = 'varname';
-    const VARTYPE = 'vartype';
-    const CONTINUE_ = 'continue';
-    const FEEDBACKTYPE = 'feedbacktype';
-    const LINKREFID = 'linkrefid';
-    const VAREQUAL = 'varequal';
-    const RESPIDENT = 'respident';
-    const ITEMFEEDBACK = 'itemfeedback';
-    const FLOW_MAT = 'flow_mat';
-    const RCARDINALITY = 'rcardinality';
-    const CHARSET = 'charset';
-    const LABEL = 'label';
-    const URI = 'uri';
-    const WIDTH = 'width';
-    const HEIGHT = 'height';
-    const X0 = 'x0';
-    const Y0 = 'y0';
-    const XML_LANG = 'lang';
-    const XML_SPACE = 'space';
-    const RUBRIC = 'rubric';
-    const ALTMATERIAL = 'altmaterial';
-    const PRESENTATION_MATERIAL = 'presentation_material';
-    const T_CLASS = 'class';
-    const MATERIAL_REF = 'material_ref';
-    const RTIMING = 'rtiming';
-    const RENDER_FIB = 'render_fib';
-    const SHUFFLE = 'shuffle';
-    const MINNUMBER = 'minnumber';
-    const MAXNUMBER = 'maxnumber';
-    const ENCODING = 'encoding';
-    const MAXCHARS = 'maxchars';
-    const PROMPT = 'prompt';
-    const FIBTYPE = 'fibtype';
-    const ROWS = 'rows';
-    const COLUMNS = 'columns';
-    const LABELREFID = 'labelrefid';
-    const RSHUFFLE = 'rshuffle';
-    const MATCH_GROUP = 'match_group';
-    const MATCH_MAX = 'match_max';
-    const FLOW = 'flow';
-    const RESPONSE_STR = 'response_str';
-    const FLOW_LABEL = 'flow_label';
-    const SETVAR = 'setvar';
-    const ACTION = 'action';
-    const AND_ = 'and';
-    const NOT_ = 'not';
-    const CASE_ = 'case';
-    const VARSUBSTRING = 'varsubstring';
-    const HINT = 'hint';
-    const SOLUTION = 'solution';
-    const FEEDBACKSTYLE = 'feedbackstyle';
-    const SOLUTIONMATERIAL = 'solutionmaterial';
-    const HINTMATERIAL = 'hintmaterial';
+    public const QUESTESTINTEROP = 'questestinterop';
+    public const ASSESSMENT = 'assessment';
+    public const QTIMETADATA = 'qtimetadata';
+    public const QTIMETADATAFIELD = 'qtimetadatafield';
+    public const FIELDLABEL = 'fieldlabel';
+    public const FIELDENTRY = 'fieldentry';
+    public const SECTION = 'section';
+    public const IDENT = 'ident';
+    public const ITEM = 'item';
+    public const TITLE = 'title';
+    public const ITEMMETADATA = 'itemmetadata';
+    public const PRESENTATION = 'presentation';
+    public const MATERIAL = 'material';
+    public const MATTEXT = 'mattext';
+    public const MATREF = 'matref';
+    public const MATBREAK = 'matbreak';
+    public const TEXTTYPE = 'texttype';
+    public const RESPONSE_LID = 'response_lid';
+    public const RENDER_CHOICE = 'render_choice';
+    public const RESPONSE_LABEL = 'response_label';
+    public const RESPROCESSING = 'resprocessing';
+    public const OUTCOMES = 'outcomes';
+    public const DECVAR = 'decvar';
+    public const RESPCONDITION = 'respcondition';
+    public const CONDITIONVAR = 'conditionvar';
+    public const OTHER = 'other';
+    public const DISPLAYFEEDBACK = 'displayfeedback';
+    public const MAXVALUE = 'maxvalue';
+    public const MINVALUE = 'minvalue';
+    public const VARNAME = 'varname';
+    public const VARTYPE = 'vartype';
+    public const CONTINUE_ = 'continue';
+    public const FEEDBACKTYPE = 'feedbacktype';
+    public const LINKREFID = 'linkrefid';
+    public const VAREQUAL = 'varequal';
+    public const RESPIDENT = 'respident';
+    public const ITEMFEEDBACK = 'itemfeedback';
+    public const FLOW_MAT = 'flow_mat';
+    public const RCARDINALITY = 'rcardinality';
+    public const CHARSET = 'charset';
+    public const LABEL = 'label';
+    public const URI = 'uri';
+    public const WIDTH = 'width';
+    public const HEIGHT = 'height';
+    public const X0 = 'x0';
+    public const Y0 = 'y0';
+    public const XML_LANG = 'lang';
+    public const XML_SPACE = 'space';
+    public const RUBRIC = 'rubric';
+    public const ALTMATERIAL = 'altmaterial';
+    public const PRESENTATION_MATERIAL = 'presentation_material';
+    public const T_CLASS = 'class';
+    public const MATERIAL_REF = 'material_ref';
+    public const RTIMING = 'rtiming';
+    public const RENDER_FIB = 'render_fib';
+    public const SHUFFLE = 'shuffle';
+    public const MINNUMBER = 'minnumber';
+    public const MAXNUMBER = 'maxnumber';
+    public const ENCODING = 'encoding';
+    public const MAXCHARS = 'maxchars';
+    public const PROMPT = 'prompt';
+    public const FIBTYPE = 'fibtype';
+    public const ROWS = 'rows';
+    public const COLUMNS = 'columns';
+    public const LABELREFID = 'labelrefid';
+    public const RSHUFFLE = 'rshuffle';
+    public const MATCH_GROUP = 'match_group';
+    public const MATCH_MAX = 'match_max';
+    public const FLOW = 'flow';
+    public const RESPONSE_STR = 'response_str';
+    public const FLOW_LABEL = 'flow_label';
+    public const SETVAR = 'setvar';
+    public const ACTION = 'action';
+    public const AND_ = 'and';
+    public const NOT_ = 'not';
+    public const CASE_ = 'case';
+    public const VARSUBSTRING = 'varsubstring';
+    public const HINT = 'hint';
+    public const SOLUTION = 'solution';
+    public const FEEDBACKSTYLE = 'feedbackstyle';
+    public const SOLUTIONMATERIAL = 'solutionmaterial';
+    public const HINTMATERIAL = 'hintmaterial';
 }
diff --git a/main/common_cartridge/export/src/lib/assesment/CcQtiValues.php b/main/common_cartridge/export/src/lib/assesment/CcQtiValues.php
index 23ab4eb324..48e6b22bc1 100644
--- a/main/common_cartridge/export/src/lib/assesment/CcQtiValues.php
+++ b/main/common_cartridge/export/src/lib/assesment/CcQtiValues.php
@@ -3,29 +3,29 @@
 
 abstract class CcQtiValues
 {
-    const EXAM_PROFILE = 'cc.exam.v0p1';
-    const YES = 'Yes';
-    const NO = 'No';
-    const RESPONSE = 'Response';
-    const SOLUTION = 'Solution';
-    const HINT = 'Hint';
-    const EXAMINATION = 'Examination';
-    const PERCENTAGE = 'Percentage';
-    const UNLIMITED = 'unlimited';
-    const SINGLE = 'Single';
-    const MULTIPLE = 'Multiple';
-    const ORDERER = 'Ordered';
-    const ASTERISK = 'Asterisk';
-    const BOX = 'Box';
-    const DASHLINE = 'Dashline';
-    const UNDERLINE = 'Underline';
-    const DECIMAL = 'Decimal';
-    const INTEGER = 'Integer';
-    const SCIENTIFIC = 'Scientific';
-    const STRING = 'String';
-    const SCORE = 'SCORE';
-    const SET = 'Set';
-    const COMPLETE = 'Complete';
-    const TEXTTYPE = 'text/plain';
-    const HTMLTYPE = 'text/html';
+    public const EXAM_PROFILE = 'cc.exam.v0p1';
+    public const YES = 'Yes';
+    public const NO = 'No';
+    public const RESPONSE = 'Response';
+    public const SOLUTION = 'Solution';
+    public const HINT = 'Hint';
+    public const EXAMINATION = 'Examination';
+    public const PERCENTAGE = 'Percentage';
+    public const UNLIMITED = 'unlimited';
+    public const SINGLE = 'Single';
+    public const MULTIPLE = 'Multiple';
+    public const ORDERER = 'Ordered';
+    public const ASTERISK = 'Asterisk';
+    public const BOX = 'Box';
+    public const DASHLINE = 'Dashline';
+    public const UNDERLINE = 'Underline';
+    public const DECIMAL = 'Decimal';
+    public const INTEGER = 'Integer';
+    public const SCIENTIFIC = 'Scientific';
+    public const STRING = 'String';
+    public const SCORE = 'SCORE';
+    public const SET = 'Set';
+    public const COMPLETE = 'Complete';
+    public const TEXTTYPE = 'text/plain';
+    public const HTMLTYPE = 'text/html';
 }
diff --git a/main/common_cartridge/export/src/lib/assesment/CcXmlNamespace.php b/main/common_cartridge/export/src/lib/assesment/CcXmlNamespace.php
index 5b11521c0b..0b976b0c7b 100644
--- a/main/common_cartridge/export/src/lib/assesment/CcXmlNamespace.php
+++ b/main/common_cartridge/export/src/lib/assesment/CcXmlNamespace.php
@@ -3,5 +3,5 @@
 
 abstract class CcXmlNamespace
 {
-    const XML = 'http://www.w3.org/XML/1998/namespace';
+    public const XML = 'http://www.w3.org/XML/1998/namespace';
 }
diff --git a/main/common_cartridge/import/Cc1p3Convert.php b/main/common_cartridge/import/Cc1p3Convert.php
index 86f5ee6ca5..cc2089ec4f 100644
--- a/main/common_cartridge/import/Cc1p3Convert.php
+++ b/main/common_cartridge/import/Cc1p3Convert.php
@@ -3,12 +3,12 @@
 
 class Cc1p3Convert extends CcBase
 {
-    const CC_TYPE_FORUM = 'imsdt_xmlv1p3';
-    const CC_TYPE_QUIZ = 'imsqti_xmlv1p3/imscc_xmlv1p3/assessment';
-    const CC_TYPE_QUESTION_BANK = 'imsqti_xmlv1p3/imscc_xmlv1p3/question-bank';
-    const CC_TYPE_WEBLINK = 'imswl_xmlv1p3';
-    const CC_TYPE_ASSOCIATED_CONTENT = 'associatedcontent/imscc_xmlv1p3/learning-application-resource';
-    const CC_TYPE_BASICLTI = 'imsbasiclti_xmlv1p3';
+    public const CC_TYPE_FORUM = 'imsdt_xmlv1p3';
+    public const CC_TYPE_QUIZ = 'imsqti_xmlv1p3/imscc_xmlv1p3/assessment';
+    public const CC_TYPE_QUESTION_BANK = 'imsqti_xmlv1p3/imscc_xmlv1p3/question-bank';
+    public const CC_TYPE_WEBLINK = 'imswl_xmlv1p3';
+    public const CC_TYPE_ASSOCIATED_CONTENT = 'associatedcontent/imscc_xmlv1p3/learning-application-resource';
+    public const CC_TYPE_BASICLTI = 'imsbasiclti_xmlv1p3';
 
     public static $namespaces = ['imscc' => 'http://www.imsglobal.org/xsd/imsccv1p3/imscp_v1p1',
                                       'lomimscc' => 'http://ltsc.ieee.org/xsd/imsccv1p3/LOM/manifest',
diff --git a/main/common_cartridge/import/Imscc13Import.php b/main/common_cartridge/import/Imscc13Import.php
index df54cb7c43..9378d1b309 100644
--- a/main/common_cartridge/import/Imscc13Import.php
+++ b/main/common_cartridge/import/Imscc13Import.php
@@ -3,7 +3,7 @@
 
 class Imscc13Import
 {
-    const FORMAT_IMSCC13 = 'imscc13';
+    public const FORMAT_IMSCC13 = 'imscc13';
 
     public function log($message, $level, $a = null, $depth = null, $display = false)
     {
diff --git a/main/common_cartridge/import/src/base/CcBase.php b/main/common_cartridge/import/src/base/CcBase.php
index 574220d6ba..9cdf090f40 100644
--- a/main/common_cartridge/import/src/base/CcBase.php
+++ b/main/common_cartridge/import/src/base/CcBase.php
@@ -3,13 +3,13 @@
 
 class CcBase
 {
-    const CC_TYPE_FORUM = 'imsdt_xmlv1p3';
-    const CC_TYPE_QUIZ = 'imsqti_xmlv1p3/imscc_xmlv1p3/assessment';
-    const CC_TYPE_QUESTION_BANK = 'imsqti_xmlv1p3/imscc_xmlv1p3/question-bank';
-    const CC_TYPE_WEBLINK = 'imswl_xmlv1p3';
-    const CC_TYPE_WEBCONTENT = 'webcontent';
-    const CC_TYPE_ASSOCIATED_CONTENT = 'associatedcontent/imscc_xmlv1p3/learning-application-resource';
-    const CC_TYPE_EMPTY = '';
+    public const CC_TYPE_FORUM = 'imsdt_xmlv1p3';
+    public const CC_TYPE_QUIZ = 'imsqti_xmlv1p3/imscc_xmlv1p3/assessment';
+    public const CC_TYPE_QUESTION_BANK = 'imsqti_xmlv1p3/imscc_xmlv1p3/question-bank';
+    public const CC_TYPE_WEBLINK = 'imswl_xmlv1p3';
+    public const CC_TYPE_WEBCONTENT = 'webcontent';
+    public const CC_TYPE_ASSOCIATED_CONTENT = 'associatedcontent/imscc_xmlv1p3/learning-application-resource';
+    public const CC_TYPE_EMPTY = '';
 
     public static $restypes = ['associatedcontent/imscc_xmlv1p0/learning-application-resource', 'webcontent'];
     public static $forumns = ['dt' => 'http://www.imsglobal.org/xsd/imsdt_v1p0'];
diff --git a/main/common_cartridge/import/src/base/validator/CcValidateType.php b/main/common_cartridge/import/src/base/validator/CcValidateType.php
index 0e5d693d09..000e354fe9 100644
--- a/main/common_cartridge/import/src/base/validator/CcValidateType.php
+++ b/main/common_cartridge/import/src/base/validator/CcValidateType.php
@@ -3,22 +3,22 @@
 
 class CcValidateType
 {
-    const MANIFEST_VALIDATOR1 = 'cclibxml2validator.xsd';
-    const ASSESMENT_VALIDATOR1 = '/domainProfile_4/ims_qtiasiv1p2_localised.xsd';
-    const DISCUSSION_VALIDATOR1 = '/domainProfile_6/imsdt_v1p0_localised.xsd';
-    const WEBLINK_VALIDATOR1 = '/domainProfile_5/imswl_v1p0_localised.xsd';
-
-    const MANIFEST_VALIDATOR11 = 'cc11libxml2validator.xsd';
-    const BLTI_VALIDATOR11 = 'imslticc_v1p0p1.xsd';
-    const ASSESMENT_VALIDATOR11 = 'ccv1p1_qtiasiv1p2p1_v1p0.xsd';
-    const DISCUSSION_VALIDATOR11 = 'ccv1p1_imsdt_v1p1.xsd';
-    const WEBLINK_VALIDATOR11 = 'ccv1p1_imswl_v1p1.xsd';
-
-    const MANIFEST_VALIDATOR13 = 'cc13libxml2validator.xsd';
-    const BLTI_VALIDATOR13 = 'imslticc_v1p3.xsd';
-    const ASSESMENT_VALIDATOR13 = 'ccv1p3_qtiasiv1p2p1_v1p0.xsd';
-    const DISCUSSION_VALIDATOR13 = 'ccv1p3_imsdt_v1p3.xsd';
-    const WEBLINK_VALIDATOR13 = 'ccv1p3_imswl_v1p3.xsd';
+    public const MANIFEST_VALIDATOR1 = 'cclibxml2validator.xsd';
+    public const ASSESMENT_VALIDATOR1 = '/domainProfile_4/ims_qtiasiv1p2_localised.xsd';
+    public const DISCUSSION_VALIDATOR1 = '/domainProfile_6/imsdt_v1p0_localised.xsd';
+    public const WEBLINK_VALIDATOR1 = '/domainProfile_5/imswl_v1p0_localised.xsd';
+
+    public const MANIFEST_VALIDATOR11 = 'cc11libxml2validator.xsd';
+    public const BLTI_VALIDATOR11 = 'imslticc_v1p0p1.xsd';
+    public const ASSESMENT_VALIDATOR11 = 'ccv1p1_qtiasiv1p2p1_v1p0.xsd';
+    public const DISCUSSION_VALIDATOR11 = 'ccv1p1_imsdt_v1p1.xsd';
+    public const WEBLINK_VALIDATOR11 = 'ccv1p1_imswl_v1p1.xsd';
+
+    public const MANIFEST_VALIDATOR13 = 'cc13libxml2validator.xsd';
+    public const BLTI_VALIDATOR13 = 'imslticc_v1p3.xsd';
+    public const ASSESMENT_VALIDATOR13 = 'ccv1p3_qtiasiv1p2p1_v1p0.xsd';
+    public const DISCUSSION_VALIDATOR13 = 'ccv1p3_imsdt_v1p3.xsd';
+    public const WEBLINK_VALIDATOR13 = 'ccv1p3_imswl_v1p3.xsd';
 
     /**
      * @var string
diff --git a/main/course_home/2column.php b/main/course_home/2column.php
index 8185826d39..347937fe4f 100755
--- a/main/course_home/2column.php
+++ b/main/course_home/2column.php
@@ -28,7 +28,7 @@ if (api_is_allowed_to_edit(null, true)) {
         $msgDestroy = get_lang('DelLk').'<br />';
         $msgDestroy .= '<a href="'.api_get_self().'">'.get_lang('No').'</a>&nbsp;|&nbsp;';
         $msgDestroy .= '<a href="'.api_get_self().'?destroy=yes&amp;id='.$id.'">'.get_lang('Yes').'</a>';
-        $show_message .= Display :: return_message($msgDestroy, 'confirmation', false);
+        $show_message .= Display::return_message($msgDestroy, 'confirmation', false);
     } elseif (isset($_GET['destroy']) && $_GET['destroy']) {
         /*
          * Process hiding a tools from available tools.
diff --git a/main/coursecopy/copy_course_session.php b/main/coursecopy/copy_course_session.php
index 4815da08c1..f2c73cea75 100755
--- a/main/coursecopy/copy_course_session.php
+++ b/main/coursecopy/copy_course_session.php
@@ -214,7 +214,7 @@ function search_courses($id_session, $type)
 
             $course_list_destination = [];
             $return .= '<select id="destination" name="SessionCoursesListDestination[]" class="form-control">';
-            while ($course = Database :: fetch_array($rs)) {
+            while ($course = Database::fetch_array($rs)) {
                 $course_list_destination[] = $course['code'];
                 $return .= '<option value="'.$course['code'].'" title="'.@htmlspecialchars($course['title'].' ('.$course['visual_code'].')', ENT_QUOTES, api_get_system_encoding()).'">'.$course['title'].' ('.$course['visual_code'].')</option>';
             }
@@ -395,7 +395,7 @@ if (Security::check_token('post') && (
         $hiddenFields['origin_session'] = $origin_session;
         // Add token to Course select form
         $hiddenFields['sec_token'] = Security::get_token();
-        CourseSelectForm :: display_form($course, $hiddenFields, true);
+        CourseSelectForm::display_form($course, $hiddenFields, true);
         echo '<div style="float:right"><a href="javascript:window.history.go(-1);">'.
             Display::return_icon(
                 'back.png',
diff --git a/main/coursecopy/copy_course_session_selected.php b/main/coursecopy/copy_course_session_selected.php
index 71b7e78706..964bf3603a 100644
--- a/main/coursecopy/copy_course_session_selected.php
+++ b/main/coursecopy/copy_course_session_selected.php
@@ -375,7 +375,7 @@ if (($action === 'course_select_form') ||
         $hiddenFields['origin_course'] = api_get_course_id();
         $hiddenFields['origin_session'] = api_get_session_id();
 
-        CourseSelectForm :: display_form($course, $hiddenFields, true);
+        CourseSelectForm::display_form($course, $hiddenFields, true);
 
         echo '<div style="float:right"><a href="javascript:window.history.go(-1);">'.
             Display::return_icon(
diff --git a/main/document/create_audio.php b/main/document/create_audio.php
index 8f61974a52..7f16e45170 100755
--- a/main/document/create_audio.php
+++ b/main/document/create_audio.php
@@ -87,7 +87,7 @@ if (!empty($groupId)) {
         "url" => "../group/group_space.php?".api_get_cidreq(),
         "name" => get_lang('GroupSpace'),
     ];
-    $group = GroupManager:: get_group_properties($groupId);
+    $group = GroupManager::get_group_properties($groupId);
     $path = explode('/', $dir);
     if ('/'.$path[1] != $group['directory']) {
         api_not_allowed(true);
@@ -142,7 +142,7 @@ if (isset($_POST['text2voice_mode']) && $_POST['text2voice_mode'] == 'google') {
     downloadAudioGoogle($filepath, $dir);
 }
 
-Display:: display_header($nameTools, 'Doc');
+Display::display_header($nameTools, 'Doc');
 
 echo '<div class="actions">';
 echo '<a href="document.php?id='.$document_id.'">';
diff --git a/main/document/create_document.php b/main/document/create_document.php
index e5a48db47b..febf4659ad 100755
--- a/main/document/create_document.php
+++ b/main/document/create_document.php
@@ -631,7 +631,7 @@ if ($form->validate()) {
         }
     }
 
-    Display :: display_header($nameTools, "Doc");
+    Display::display_header($nameTools, "Doc");
     // link back to the documents overview
     if ($is_certificate_mode) {
         $actionsLeft = '<a href="document.php?'.api_get_cidreq().'&certificate=true&id='.$folder_id.'&selectcat='.$select_cat.'">'.
@@ -678,5 +678,5 @@ if ($form->validate()) {
                 '.$form->returnForm().'
             </div>
           </div></div>';
-    Display :: display_footer();
+    Display::display_footer();
 }
diff --git a/main/document/create_draw.php b/main/document/create_draw.php
index 613ef6ac9a..85a3a508d2 100755
--- a/main/document/create_draw.php
+++ b/main/document/create_draw.php
@@ -83,7 +83,7 @@ if (!empty($groupId)) {
         "url" => "../group/group_space.php?".api_get_cidreq(),
         "name" => get_lang('GroupSpace'),
     ];
-    $group = GroupManager :: get_group_properties($groupId);
+    $group = GroupManager::get_group_properties($groupId);
     $path = explode('/', $dir);
     if ('/'.$path[1] != $group['directory']) {
         api_not_allowed(true);
@@ -134,7 +134,7 @@ if (empty($document_data['parents'])) {
         ];
     }
 }
-Display :: display_header($nameTools, 'Doc');
+Display::display_header($nameTools, 'Doc');
 
 echo '<div class="actions">';
 echo '<a href="document.php?id='.$document_id.'">'.
@@ -169,4 +169,4 @@ if (api_browser_support('svg')) {
     echo Display::return_message(get_lang('BrowserDontSupportsSVG'), 'error');
 }
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/document/edit_document.php b/main/document/edit_document.php
index f632e1cfbb..aaa38cb82a 100755
--- a/main/document/edit_document.php
+++ b/main/document/edit_document.php
@@ -375,7 +375,7 @@ $groupInfo = GroupManager::get_group_properties(api_get_group_id());
 
 if ($owner_id == api_get_user_id() ||
     api_is_platform_admin() ||
-    $is_allowed_to_edit || GroupManager:: is_user_in_group(
+    $is_allowed_to_edit || GroupManager::is_user_in_group(
         api_get_user_id(),
         $groupInfo
     )
diff --git a/main/document/edit_draw.php b/main/document/edit_draw.php
index 2b85a85ec2..4826f24f0c 100755
--- a/main/document/edit_draw.php
+++ b/main/document/edit_draw.php
@@ -130,7 +130,7 @@ if (!$is_allowedToEdit) {
 
 Event::event_access_tool(TOOL_DOCUMENT);
 
-Display :: display_header($nameTools, 'Doc');
+Display::display_header($nameTools, 'Doc');
 echo '<div class="actions">';
 echo '<a href="document.php?id='.$parent_id.'">'.
     Display::return_icon('back.png', get_lang('BackTo').' '.get_lang('DocumentsOverview'), '', ICON_SIZE_MEDIUM).'</a>';
diff --git a/main/document/edit_paint.php b/main/document/edit_paint.php
index f49cbf4c4b..53636376eb 100755
--- a/main/document/edit_paint.php
+++ b/main/document/edit_paint.php
@@ -125,7 +125,7 @@ if (!$is_allowedToEdit) {
 
 Event::event_access_tool(TOOL_DOCUMENT);
 
-Display :: display_header($nameTools, 'Doc');
+Display::display_header($nameTools, 'Doc');
 echo '<div class="actions">';
 echo '<a href="document.php?id='.$parent_id.'&'.api_get_cidreq().'">'.
     Display::return_icon('back.png', get_lang('BackTo').' '.get_lang('DocumentsOverview'), '', ICON_SIZE_MEDIUM).'</a>';
diff --git a/main/document/save_pixlr.php b/main/document/save_pixlr.php
index be48e8cd1f..0938d51849 100755
--- a/main/document/save_pixlr.php
+++ b/main/document/save_pixlr.php
@@ -123,7 +123,7 @@ $temp_file_2delete = Session::read('temp_realpath_image');
 if (empty($temp_file_2delete)) {
     // Create file
     if (0 != $groupId) {
-        $group_properties = GroupManager :: get_group_properties($groupId);
+        $group_properties = GroupManager::get_group_properties($groupId);
         $groupPath = $group_properties['directory'];
     } else {
         $groupPath = '';
diff --git a/main/dropbox/dropbox_functions.inc.php b/main/dropbox/dropbox_functions.inc.php
index 6a7e282f76..7cebd0eb17 100755
--- a/main/dropbox/dropbox_functions.inc.php
+++ b/main/dropbox/dropbox_functions.inc.php
@@ -562,7 +562,7 @@ function display_add_form($viewReceivedCategory, $viewSentCategory, $view, $id =
     if (api_get_session_id()) {
         $complete_user_list_for_dropbox = [];
         if (api_get_setting('dropbox_allow_student_to_student') == 'true' || $_user['status'] != STUDENT) {
-            $complete_user_list_for_dropbox = CourseManager:: get_user_list_from_course_code(
+            $complete_user_list_for_dropbox = CourseManager::get_user_list_from_course_code(
                 $course_info['code'],
                 api_get_session_id(),
                 null,
diff --git a/main/exercise/MultipleAnswerTrueFalseDegreeCertainty.php b/main/exercise/MultipleAnswerTrueFalseDegreeCertainty.php
index 6d76e0cb4c..12535118cf 100644
--- a/main/exercise/MultipleAnswerTrueFalseDegreeCertainty.php
+++ b/main/exercise/MultipleAnswerTrueFalseDegreeCertainty.php
@@ -11,11 +11,11 @@ use ChamiloSession as Session;
  */
 class MultipleAnswerTrueFalseDegreeCertainty extends Question
 {
-    const LEVEL_DARKGREEN = 1;
-    const LEVEL_LIGHTGREEN = 2;
-    const LEVEL_WHITE = 3;
-    const LEVEL_LIGHTRED = 4;
-    const LEVEL_DARKRED = 5;
+    public const LEVEL_DARKGREEN = 1;
+    public const LEVEL_LIGHTGREEN = 2;
+    public const LEVEL_WHITE = 3;
+    public const LEVEL_LIGHTRED = 4;
+    public const LEVEL_DARKRED = 5;
 
     public $typePicture = 'mccert.png';
     public $explanationLangVar = 'MultipleAnswerTrueFalseDegreeCertainty';
diff --git a/main/exercise/comparative_group_report.php b/main/exercise/comparative_group_report.php
index 6a53aa034c..6df10b46d2 100644
--- a/main/exercise/comparative_group_report.php
+++ b/main/exercise/comparative_group_report.php
@@ -85,7 +85,7 @@ if ($exportXls) {
 }
 Display::display_header($nameTools, get_lang('Exercise'));
 $actions = '<a href="exercise_report.php?exerciseId='.$exerciseId.'&'.api_get_cidreq().'">'.
-    Display:: return_icon(
+    Display::return_icon(
         'back.png',
         get_lang('GoBackToQuestionList'),
         '',
diff --git a/main/exercise/exercise.class.php b/main/exercise/exercise.class.php
index 19728f6a3e..a48a37c471 100755
--- a/main/exercise/exercise.class.php
+++ b/main/exercise/exercise.class.php
@@ -9309,7 +9309,7 @@ class Exercise
                         c_id = $courseId AND
                         path LIKE '".Database::escape_string($uploadPath.'/%/%')."'";
             $res = Database::query($sql);
-            $hp_count = Database :: num_rows($res);
+            $hp_count = Database::num_rows($res);
         } else {
             $sql = "SELECT * FROM $TBL_DOCUMENT d
                     INNER JOIN $TBL_ITEM_PROPERTY ip
@@ -9882,7 +9882,7 @@ class Exercise
                                 ORDER BY exe_id DESC";
 
                         $qryres = Database::query($sql);
-                        $num = Database :: num_rows($qryres);
+                        $num = Database::num_rows($qryres);
 
                         // Hide the results.
                         $my_result_disabled = $row['results_disabled'];
@@ -9906,7 +9906,7 @@ class Exercise
                                 ) {
                                     // More than one attempt
                                     if ($num > 0) {
-                                        $row_track = Database :: fetch_array($qryres);
+                                        $row_track = Database::fetch_array($qryres);
                                         $attempt_text = get_lang('LatestAttempt').' : ';
                                         $attempt_text .= ExerciseLib::show_score(
                                             $row_track['exe_result'],
@@ -9973,7 +9973,7 @@ class Exercise
                             )
                             ) {
                                 if ($num > 0) {
-                                    $row_track = Database :: fetch_array($qryres);
+                                    $row_track = Database::fetch_array($qryres);
                                     $attempt_text = get_lang('LatestAttempt').' : ';
                                     $attempt_text .= ExerciseLib::show_score(
                                         $row_track['exe_result'],
@@ -10053,7 +10053,7 @@ class Exercise
                     WHERE
                         d.c_id = $courseId AND
                         (d.path LIKE '%htm%') AND
-                        d.path  LIKE '".Database :: escape_string($uploadPath.'/%/%')."'
+                        d.path  LIKE '".Database::escape_string($uploadPath.'/%/%')."'
                     LIMIT $from , $limit"; // only .htm or .html files listed
         } else {
             $sql = "SELECT d.iid, d.path as path, d.comment as comment
@@ -10061,7 +10061,7 @@ class Exercise
                     WHERE
                         d.c_id = $courseId AND
                         (d.path LIKE '%htm%') AND
-                        d.path  LIKE '".Database :: escape_string($uploadPath.'/%/%')."'
+                        d.path  LIKE '".Database::escape_string($uploadPath.'/%/%')."'
                     LIMIT $from , $limit";
         }
 
diff --git a/main/exercise/exercise.php b/main/exercise/exercise.php
index 3a74509776..9b117b9df4 100644
--- a/main/exercise/exercise.php
+++ b/main/exercise/exercise.php
@@ -583,7 +583,7 @@ if ($is_allowedToEdit) {
                 $query = "SELECT iid FROM $TBL_DOCUMENT
                           WHERE c_id = $courseId AND path='".Database::escape_string($file)."'";
                 $res = Database::query($query);
-                $row = Database :: fetch_array($res, 'ASSOC');
+                $row = Database::fetch_array($res, 'ASSOC');
                 api_item_property_update(
                     $courseInfo,
                     TOOL_DOCUMENT,
@@ -604,7 +604,7 @@ if ($is_allowedToEdit) {
                 $query = "SELECT iid FROM $TBL_DOCUMENT
                           WHERE c_id = $courseId AND path='".Database::escape_string($file)."'";
                 $res = Database::query($query);
-                $row = Database :: fetch_array($res, 'ASSOC');
+                $row = Database::fetch_array($res, 'ASSOC');
                 api_item_property_update(
                     $courseInfo,
                     TOOL_DOCUMENT,
diff --git a/main/exercise/exercise_report.php b/main/exercise/exercise_report.php
index 49052cd678..4da9cdb638 100755
--- a/main/exercise/exercise_report.php
+++ b/main/exercise/exercise_report.php
@@ -251,7 +251,7 @@ if (isset($_REQUEST['comments']) &&
                 GROUP BY question_id';
         $res = Database::query($qry);
         $tot = 0;
-        while ($row = Database :: fetch_array($res, 'ASSOC')) {
+        while ($row = Database::fetch_array($res, 'ASSOC')) {
             $marks = $row['marks'];
             if (!$objExerciseTmp->propagate_neg && $marks < 0) {
                 continue;
diff --git a/main/exercise/exercise_result.class.php b/main/exercise/exercise_result.class.php
index 795251f38e..2b67e5d6c2 100755
--- a/main/exercise/exercise_result.class.php
+++ b/main/exercise/exercise_result.class.php
@@ -206,7 +206,7 @@ class ExerciseResult
                                 LIMIT 1";
                     $query = Database::query($sql_exe);
 
-                    if (Database:: num_rows($query) > 0) {
+                    if (Database::num_rows($query) > 0) {
                         $revised = 1;
                     }
                 }
@@ -661,7 +661,7 @@ class ExerciseResult
                     strip_tags(
                         implode(
                             ", ",
-                            GroupManager:: get_user_group_name($row['user_id'])
+                            GroupManager::get_user_group_name($row['user_id'])
                         )
                     ),
                     ENT_QUOTES,
diff --git a/main/exercise/exercise_submit.php b/main/exercise/exercise_submit.php
index a2d5f47f99..45e2b97b92 100755
--- a/main/exercise/exercise_submit.php
+++ b/main/exercise/exercise_submit.php
@@ -1131,7 +1131,7 @@ if (isset($_custom['exercises_hidden_when_no_start_date']) &&
     $_custom['exercises_hidden_when_no_start_date']
 ) {
     if (empty($objExercise->start_time)) {
-        echo Display:: return_message(
+        echo Display::return_message(
             sprintf(
                 get_lang('ExerciseNoStartedYet'),
                 $exercise_title,
diff --git a/main/exercise/fill_blanks.class.php b/main/exercise/fill_blanks.class.php
index 7ae831a95a..267464392a 100755
--- a/main/exercise/fill_blanks.class.php
+++ b/main/exercise/fill_blanks.class.php
@@ -10,9 +10,9 @@
  */
 class FillBlanks extends Question
 {
-    const FILL_THE_BLANK_STANDARD = 0;
-    const FILL_THE_BLANK_MENU = 1;
-    const FILL_THE_BLANK_SEVERAL_ANSWER = 2;
+    public const FILL_THE_BLANK_STANDARD = 0;
+    public const FILL_THE_BLANK_MENU = 1;
+    public const FILL_THE_BLANK_SEVERAL_ANSWER = 2;
 
     public $typePicture = 'fill_in_blanks.png';
     public $explanationLangVar = 'FillBlanks';
diff --git a/main/exercise/hotpotatoes_exercise_report.php b/main/exercise/hotpotatoes_exercise_report.php
index 12278bad92..7f2b7536cf 100755
--- a/main/exercise/hotpotatoes_exercise_report.php
+++ b/main/exercise/hotpotatoes_exercise_report.php
@@ -103,7 +103,7 @@ if ($is_allowedToEdit || $is_tutor) {
     $objExerciseTmp = new Exercise();
 }
 
-Display :: display_header($nameTools);
+Display::display_header($nameTools);
 $actions = Display::div($actions, ['class' => 'actions']);
 
 $extra = '<script>
@@ -325,4 +325,4 @@ $(function() {
 <?php
 
 echo Display::grid_html('results');
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/exercise/question_create.php b/main/exercise/question_create.php
index 14db2c8810..abe39be63a 100755
--- a/main/exercise/question_create.php
+++ b/main/exercise/question_create.php
@@ -53,7 +53,7 @@ $sql = "SELECT iid, title, type, description, results_disabled
         ORDER BY title ASC";
 $result = Database::query($sql);
 $exercises['-'] = '-'.get_lang('SelectExercise').'-';
-while ($row = Database :: fetch_array($result)) {
+while ($row = Database::fetch_array($result)) {
     $exercises[$row['iid']] = cut($row['title'], EXERCISE_MAX_NAME_SIZE);
 }
 $form->addElement('select', 'exercise', get_lang('Exercise'), $exercises);
diff --git a/main/exercise/question_stats.php b/main/exercise/question_stats.php
index 733c9018a6..9c8337ebc6 100644
--- a/main/exercise/question_stats.php
+++ b/main/exercise/question_stats.php
@@ -188,7 +188,7 @@ $htmlHeadXtra[] = '<script>
 
 Display::display_header($nameTools, get_lang('Exercise'));
 $actions = '<a href="exercise_report.php?exerciseId='.$exerciseId.'&'.api_get_cidreq().'">'.
-    Display:: return_icon(
+    Display::return_icon(
         'back.png',
         get_lang('GoBackToQuestionList'),
         '',
diff --git a/main/exercise/stats.php b/main/exercise/stats.php
index f6645d8d64..b1473489c7 100755
--- a/main/exercise/stats.php
+++ b/main/exercise/stats.php
@@ -366,7 +366,7 @@ $interbreadcrumb[] = [
 
 $tpl = new Template(get_lang('ReportByQuestion'));
 $actions = '<a href="exercise_report.php?exerciseId='.$exerciseId.'&'.api_get_cidreq().'">'.
-    Display:: return_icon(
+    Display::return_icon(
         'back.png',
         get_lang('GoBackToQuestionList'),
         '',
diff --git a/main/extra/create_exam.php b/main/extra/create_exam.php
index e112375e70..921251fdd3 100644
--- a/main/extra/create_exam.php
+++ b/main/extra/create_exam.php
@@ -8,7 +8,7 @@ if (empty($allow)) {
     exit;
 }
 
-$table = Database:: get_main_table(TABLE_STATISTIC_TRACK_E_EXERCISES);
+$table = Database::get_main_table(TABLE_STATISTIC_TRACK_E_EXERCISES);
 $ex_user_id = isset($_GET['ex_user_id']) ? (int) $_GET['ex_user_id'] : '';
 $mod_no = isset($_GET['mod_no']) ? Database::escape_string($_GET['mod_no']) : '';
 $score_ex = isset($_GET['score_ex']) ? Database::escape_string($_GET['score_ex']) : '';
diff --git a/main/extra/edit_intervention.php b/main/extra/edit_intervention.php
index 1645e6ab73..d84150a217 100644
--- a/main/extra/edit_intervention.php
+++ b/main/extra/edit_intervention.php
@@ -13,7 +13,7 @@ api_block_anonymous_users();
 Display::display_header();
 $num = isset($_GET['num']) ? (int) $_GET['num'] : 0;
 $student_idd = isset($_GET['student_id']) ? (int) $_GET['student_id'] : 0;
-$tbl_stats_exercices = Database:: get_main_table(TABLE_STATISTIC_TRACK_E_EXERCISES);
+$tbl_stats_exercices = Database::get_main_table(TABLE_STATISTIC_TRACK_E_EXERCISES);
 
 ?>
 <form action="update_intervention.php" method="post" name="save_intercention">
diff --git a/main/extra/group_space_tracking.php b/main/extra/group_space_tracking.php
index d4f2aef1e1..87cf9a61c3 100644
--- a/main/extra/group_space_tracking.php
+++ b/main/extra/group_space_tracking.php
@@ -18,12 +18,12 @@ require_once api_get_path(SYS_CODE_PATH).'forum/forumfunction.inc.php';
 /*  MAIN CODE */
 $group_id = api_get_group_id();
 $user_id = api_get_user_id();
-$current_group = GroupManager:: get_group_properties($group_id);
+$current_group = GroupManager::get_group_properties($group_id);
 // regroup table names for maintenance purpose
 if (!api_is_allowed_to_edit(false, true) && !$is_group_member) {
     api_not_allowed(true);
 }
-$tbl_stats_exercices_temp = Database:: get_main_table(track_e_exercices_temp);
+$tbl_stats_exercices_temp = Database::get_main_table(track_e_exercices_temp);
 //on vide la table temp qui recoit les examen complétés
 $query = "TRUNCATE TABLE $tbl_stats_exercices_temp ";
 $result = Database::query($query);
@@ -151,15 +151,15 @@ $table->set_header(10, get_lang('GroupCalendar'), false, 'align="center"');
 $table->set_header(11, get_lang('Details'), false);
 
 // Database table definition
-$table_group_user = Database:: get_course_table(TABLE_GROUP_USER);
-$table_user = Database:: get_main_table(TABLE_MAIN_USER);
+$table_group_user = Database::get_course_table(TABLE_GROUP_USER);
+$table_user = Database::get_main_table(TABLE_MAIN_USER);
 
 //  $tbl_personal_agenda = Database :: get_user_personal_table(TABLE_PERSONAL_AGENDA);
-$tbl_personal_agenda = Database:: get_main_table(TABLE_PERSONAL_AGENDA);
-$tbl_course = Database:: get_main_table(TABLE_MAIN_COURSE);
-$tbl_stats_exercices = Database:: get_main_table(TABLE_STATISTIC_TRACK_E_EXERCISES);
-$tbl_stats_exercices_temp = Database:: get_main_table(track_e_exercices_temp);
-$tbl_group_course_info = Database:: get_course_table(TABLE_GROUP);
+$tbl_personal_agenda = Database::get_main_table(TABLE_PERSONAL_AGENDA);
+$tbl_course = Database::get_main_table(TABLE_MAIN_COURSE);
+$tbl_stats_exercices = Database::get_main_table(TABLE_STATISTIC_TRACK_E_EXERCISES);
+$tbl_stats_exercices_temp = Database::get_main_table(track_e_exercices_temp);
+$tbl_group_course_info = Database::get_course_table(TABLE_GROUP);
 $course_id = api_get_course_int_id();
 
 //on trouve le vrai groupID
@@ -365,7 +365,7 @@ while ($resulta = Database::fetch_array($result)) {
     }
 
     $diff = abs($diff);
-    $last_connection_date = Tracking:: get_last_connection_date($user_in_groupe, true);
+    $last_connection_date = Tracking::get_last_connection_date($user_in_groupe, true);
     if ($last_connection_date == '') {
         $last_connection_date = get_lang('NoConnexion');
     }
diff --git a/main/extra/myStudents.php b/main/extra/myStudents.php
index 71f6278bba..a54f206ad4 100644
--- a/main/extra/myStudents.php
+++ b/main/extra/myStudents.php
@@ -162,12 +162,12 @@ if (isset($_GET['details'])) {
 }
 
 // Database Table Definitions
-$tbl_course_user = Database:: get_main_table(TABLE_MAIN_COURSE_USER);
-$tbl_stats_access = Database:: get_main_table(TABLE_STATISTIC_TRACK_E_ACCESS);
-$tbl_stats_exercices = Database:: get_main_table(TABLE_STATISTIC_TRACK_E_EXERCISES);
-$tbl_personal_agenda = Database:: get_main_table(TABLE_PERSONAL_AGENDA);
+$tbl_course_user = Database::get_main_table(TABLE_MAIN_COURSE_USER);
+$tbl_stats_access = Database::get_main_table(TABLE_STATISTIC_TRACK_E_ACCESS);
+$tbl_stats_exercices = Database::get_main_table(TABLE_STATISTIC_TRACK_E_EXERCISES);
+$tbl_personal_agenda = Database::get_main_table(TABLE_PERSONAL_AGENDA);
 
-$TABLECALHORAIRE = Database:: get_course_table(TABLE_CAL_HORAIRE);
+$TABLECALHORAIRE = Database::get_course_table(TABLE_CAL_HORAIRE);
 
 if (isset($_GET['user_id']) && $_GET['user_id'] != '') {
     $user_id = intval($_GET['user_id']);
@@ -244,7 +244,7 @@ if (api_is_session_admin() || api_is_drh()) {
 
     if (!empty($session_by_session_admin)) {
         foreach ($session_by_session_admin as $session_coached_by_user) {
-            $courses_followed_by_coach = Tracking:: get_courses_list_from_session($session_coached_by_user['id']);
+            $courses_followed_by_coach = Tracking::get_courses_list_from_session($session_coached_by_user['id']);
             $courses_in_session_by_coach[$session_coached_by_user['id']] = $courses_followed_by_coach;
         }
     }
@@ -266,7 +266,7 @@ $sql = "SELECT c_id
             user_id = ".intval($user_info['user_id']);
 $rs = Database::query($sql);
 
-while ($row = Database:: fetch_array($rs)) {
+while ($row = Database::fetch_array($rs)) {
     if ($drh_can_access_all_courses) {
         $courses_in_session[0][] = $row['c_id'];
     } else {
@@ -282,7 +282,7 @@ $sql = 'SELECT session_id, c_id
         WHERE user_id='.intval($user_info['user_id']);
 $rs = Database::query($sql);
 $tmp_sessions = [];
-while ($row = Database:: fetch_array($rs, 'ASSOC')) {
+while ($row = Database::fetch_array($rs, 'ASSOC')) {
     $tmp_sessions[] = $row['session_id'];
     if ($drh_can_access_all_courses) {
         if (in_array($row['session_id'], $tmp_sessions)) {
@@ -332,23 +332,23 @@ if (!empty($studentId)) {
     echo '<a href="javascript: void(0);" onclick="javascript: window.print();">'.
         Display::return_icon('printer.png', get_lang('Print'), '', ICON_SIZE_MEDIUM).'</a>';
 
-    echo '<a href="'.api_get_self().'?'.Security:: remove_XSS($_SERVER['QUERY_STRING']).'&export=csv">'.
+    echo '<a href="'.api_get_self().'?'.Security::remove_XSS($_SERVER['QUERY_STRING']).'&export=csv">'.
         Display::return_icon('export_csv.png', get_lang('ExportAsCSV'), '', ICON_SIZE_MEDIUM).'</a> ';
 
-    echo '<a href="'.api_get_self().'?'.Security:: remove_XSS($_SERVER['QUERY_STRING']).'&export=xls">'.
+    echo '<a href="'.api_get_self().'?'.Security::remove_XSS($_SERVER['QUERY_STRING']).'&export=xls">'.
         Display::return_icon('export_excel.png', get_lang('ExportAsXLS'), '', ICON_SIZE_MEDIUM).'</a> ';
 
     if (!empty($user_info['email'])) {
         $send_mail = '<a href="mailto:'.$user_info['email'].'">'.
-            Display:: return_icon('mail_send.png', get_lang('SendMail'), '', ICON_SIZE_MEDIUM).'</a>';
+            Display::return_icon('mail_send.png', get_lang('SendMail'), '', ICON_SIZE_MEDIUM).'</a>';
     } else {
-        $send_mail = Display:: return_icon('mail_send_na.png', get_lang('SendMail'), '', ICON_SIZE_MEDIUM);
+        $send_mail = Display::return_icon('mail_send_na.png', get_lang('SendMail'), '', ICON_SIZE_MEDIUM);
     }
     echo $send_mail;
     if (!empty($studentId) && !empty($course_code)) {
         // Only show link to connection details if course and student were defined in the URL
         echo '<a href="access_details.php?student='.$studentId.'&course='.$course_code.'&origin='.$origin.'&cidReq='.$course_code.'&id_session='.$sessionId.'">'.
-            Display:: return_icon('statistics.png', get_lang('AccessDetails'), '', ICON_SIZE_MEDIUM).'</a>';
+            Display::return_icon('statistics.png', get_lang('AccessDetails'), '', ICON_SIZE_MEDIUM).'</a>';
     }
     if (api_can_login_as($studentId)) {
         echo '<a href="'.api_get_path(
@@ -372,7 +372,7 @@ if (!empty($studentId)) {
 
     // get average of score and average of progress by student
     $avg_student_progress = $avg_student_score = 0;
-    if (CourseManager:: is_user_subscribed_in_course($user_info['user_id'], $course_code, true)) {
+    if (CourseManager::is_user_subscribed_in_course($user_info['user_id'], $course_code, true)) {
         $avg_student_progress = Tracking::get_avg_student_progress(
             $user_info['user_id'],
             $course_code,
@@ -393,7 +393,7 @@ if (!empty($studentId)) {
     $time_spent_on_the_course = 0;
     if (!empty($courseInfo)) {
         $time_spent_on_the_course = api_time_to_hms(
-            Tracking:: get_time_spent_on_the_course(
+            Tracking::get_time_spent_on_the_course(
                 $user_info['user_id'],
                 $courseInfo['real_id'],
                 $sessionId
@@ -402,12 +402,12 @@ if (!empty($studentId)) {
     }
 
     // get information about connections on the platform by student
-    $first_connection_date = Tracking:: get_first_connection_date($user_info['user_id']);
+    $first_connection_date = Tracking::get_first_connection_date($user_info['user_id']);
     if ($first_connection_date == '') {
         $first_connection_date = get_lang('NoConnexion');
     }
 
-    $last_connection_date = Tracking:: get_last_connection_date($user_info['user_id'], true);
+    $last_connection_date = Tracking::get_last_connection_date($user_info['user_id'], true);
     if ($last_connection_date == '') {
         $last_connection_date = get_lang('NoConnexion');
     }
@@ -550,7 +550,7 @@ if (!empty($studentId)) {
                         <td align="right">
                             <?php
                             echo get_lang('Progress').' ';
-        Display:: display_icon(
+        Display::display_icon(
                                 'info3.gif',
                                 get_lang('ScormAndLPProgressTotalAverage'),
                                 ['align' => 'absmiddle', 'hspace' => '3px']
@@ -562,7 +562,7 @@ if (!empty($studentId)) {
                         <td align="right">
                             <?php
                             echo get_lang('Score').' ';
-        Display:: display_icon(
+        Display::display_icon(
                                 'info3.gif',
                                 get_lang('ScormAndLPTestTotalAverage'),
                                 ['align' => 'absmiddle', 'hspace' => '3px']
@@ -700,9 +700,9 @@ if (!empty($studentId)) {
                     $courseId = $courseInfoItem['real_id'];
                     $courseCodeItem = $courseInfoItem['code'];
 
-                    if (CourseManager:: is_user_subscribed_in_course($studentId, $courseCodeItem, true)) {
+                    if (CourseManager::is_user_subscribed_in_course($studentId, $courseCodeItem, true)) {
                         $time_spent_on_course = api_time_to_hms(
-                            Tracking:: get_time_spent_on_the_course($user_info['user_id'], $courseId, $sId)
+                            Tracking::get_time_spent_on_the_course($user_info['user_id'], $courseId, $sId)
                         );
 
                         // get average of faults in attendances by student
@@ -755,7 +755,7 @@ if (!empty($studentId)) {
                             $sId
                         );
 
-                        $score = Tracking:: get_avg_student_score($user_info['user_id'], $courseCodeItem, [], $sId);
+                        $score = Tracking::get_avg_student_score($user_info['user_id'], $courseCodeItem, [], $sId);
                         $progress = empty($progress) ? '0%' : $progress.'%';
                         $score = empty($score) ? '0%' : $score.'%';
 
@@ -802,7 +802,7 @@ if (!empty($studentId)) {
         if ($user_info['status'] != INVITEE) {
             $csv_content[] = [];
             $csv_content[] = [str_replace('&nbsp;', '', $table_title)];
-            $t_lp = Database:: get_course_table(TABLE_LP_MAIN);
+            $t_lp = Database::get_course_table(TABLE_LP_MAIN);
 
             // csv export headers
             $csv_content[] = [];
@@ -853,7 +853,7 @@ if (!empty($studentId)) {
                             <th>
                                 <?php
                                 echo get_lang('Time').' ';
-                Display:: display_icon(
+                Display::display_icon(
                                     'info3.gif',
                                     get_lang('TotalTimeByCourse'),
                                     ['align' => 'absmiddle', 'hspace' => '3px']
@@ -862,7 +862,7 @@ if (!empty($studentId)) {
                             <th>
                                 <?php
                                 echo get_lang('AverageScore').' ';
-                Display:: display_icon(
+                Display::display_icon(
                                     'info3.gif',
                                     get_lang('AverageIsCalculatedBasedInAllAttempts'),
                                     ['align' => 'absmiddle', 'hspace' => '3px']
@@ -878,7 +878,7 @@ if (!empty($studentId)) {
                             </th>
                             <th><?php
                                 echo get_lang('Progress').' ';
-                Display:: display_icon(
+                Display::display_icon(
                                     'info3.gif',
                                     get_lang('LPProgressScore'),
                                     ['align' => 'absmiddle', 'hspace' => '3px']
@@ -886,7 +886,7 @@ if (!empty($studentId)) {
                             </th>
                             <th><?php
                                 echo get_lang('LastConnexion').' ';
-                Display:: display_icon(
+                Display::display_icon(
                                     'info3.gif',
                                     get_lang('LastTimeTheCourseWasUsed'),
                                     ['align' => 'absmiddle', 'hspace' => '3px']
@@ -961,7 +961,7 @@ if (!empty($studentId)) {
                             );
 
                     // Latest exercise results in a LP
-                    $score_latest = Tracking:: get_avg_student_score(
+                    $score_latest = Tracking::get_avg_student_score(
                                 $studentId,
                                 $course_code,
                                 [$lp_id],
@@ -1070,7 +1070,7 @@ if (!empty($studentId)) {
                     <tr>
                         <th><?php echo get_lang('Exercises'); ?></th>
                         <th><?php echo get_lang('LearningPath'); ?></th>
-                        <th><?php echo get_lang('AvgCourseScore').' '.Display:: return_icon(
+                        <th><?php echo get_lang('AvgCourseScore').' '.Display::return_icon(
                                     'info3.gif',
                                     get_lang('AverageScore'),
                                     ['align' => 'absmiddle', 'hspace' => '3px']
@@ -1090,7 +1090,7 @@ if (!empty($studentId)) {
                         get_lang('Attempts'),
                     ];
 
-            $t_quiz = Database:: get_course_table(TABLE_QUIZ_TEST);
+            $t_quiz = Database::get_course_table(TABLE_QUIZ_TEST);
             $sessionCondition = api_get_session_condition(
                 $sessionId,
                 true,
@@ -1107,8 +1107,8 @@ if (!empty($studentId)) {
 
             $result_exercices = Database::query($sql);
             $i = 0;
-            if (Database:: num_rows($result_exercices) > 0) {
-                while ($exercices = Database:: fetch_array($result_exercices)) {
+            if (Database::num_rows($result_exercices) > 0) {
+                while ($exercices = Database::fetch_array($result_exercices)) {
                     $exercise_id = intval($exercices['iid']);
                     $count_attempts = Tracking::count_student_exercise_attempts(
                                 $studentId,
@@ -1183,8 +1183,8 @@ if (!empty($studentId)) {
                             ORDER BY exe_date DESC
                             LIMIT 1";
                     $result_last_attempt = Database::query($sql);
-                    if (Database:: num_rows($result_last_attempt) > 0) {
-                        $id_last_attempt = Database:: result($result_last_attempt, 0, 0);
+                    if (Database::num_rows($result_last_attempt) > 0) {
+                        $id_last_attempt = Database::result($result_last_attempt, 0, 0);
                         if ($count_attempts > 0) {
                             echo '<a href="../exercise/exercise_show.php?id='.$id_last_attempt.
                                 '&cidReq='.$course_code.
@@ -1465,7 +1465,7 @@ while ($a_courses = Database::fetch_array($result2)) {
 }
 
 api_display_tool_title($nameTools);
-$tbl_personal_agenda = Database:: get_main_table(TABLE_PERSONAL_AGENDA);
+$tbl_personal_agenda = Database::get_main_table(TABLE_PERSONAL_AGENDA);
 $now = date('Y-m-d');
 //on compte le nombre de m% dans l'agenda pour chaque module
 $sqljtot = "SELECT COUNT( * ) AS TOT
@@ -1662,7 +1662,7 @@ if ($end_date < '2010-01-01') {
         </tr>
 
         <?php
-        $tbl_stats_exercices = Database:: get_main_table(TABLE_STATISTIC_TRACK_E_EXERCISES);
+        $tbl_stats_exercices = Database::get_main_table(TABLE_STATISTIC_TRACK_E_EXERCISES);
         $sqlinter = "SELECT *
                      FROM $tbl_stats_exercices
                      WHERE
@@ -1788,10 +1788,10 @@ if (empty($_GET['details'])) {
 
         if (!empty($courses)) {
             foreach ($courses as $course_code) {
-                if (CourseManager:: is_user_subscribed_in_course($studentId, $course_code, true)) {
-                    $course_info = CourseManager:: get_course_information($course_code);
+                if (CourseManager::is_user_subscribed_in_course($studentId, $course_code, true)) {
+                    $course_info = CourseManager::get_course_information($course_code);
                     $time_spent_on_course = api_time_to_hms(
-                        Tracking:: get_time_spent_on_the_course($user_info['user_id'], $course_code, $session_id)
+                        Tracking::get_time_spent_on_the_course($user_info['user_id'], $course_code, $session_id)
                     );
                     //on sort le c_id avec le code du cours
                     $sql8 = "SELECT *
@@ -1895,7 +1895,7 @@ if (empty($_GET['details'])) {
                         null,
                         $session_id
                     );
-                    $score = Tracking:: get_avg_student_score($user_info['user_id'], $course_code, null, $session_id);
+                    $score = Tracking::get_avg_student_score($user_info['user_id'], $course_code, null, $session_id);
                     $progress = empty($progress) ? '0%' : $progress.'%';
                     $score = empty($score) ? '0%' : $score.'%';
 
@@ -1947,7 +1947,7 @@ if (empty($_GET['details'])) {
 } else {
     $csv_content[] = [];
     $csv_content[] = [str_replace('&nbsp;', '', $table_title)];
-    $t_lp = Database:: get_course_table(TABLE_LP_MAIN);
+    $t_lp = Database::get_course_table(TABLE_LP_MAIN);
 
     // csv export headers
     $csv_content[] = [];
@@ -1975,7 +1975,7 @@ if (empty($_GET['details'])) {
     }
 
     $rs_lp = Database::query($sql_lp);
-    if (Database:: num_rows($rs_lp) > 0) {
+    if (Database::num_rows($rs_lp) > 0) {
         ?>
         <!-- LPs-->
         <table class="table table-hover table-striped data_table">
@@ -1983,31 +1983,31 @@ if (empty($_GET['details'])) {
             <th><?php echo get_lang('Learnpaths'); ?></th>
             <th><?php echo get_lang('FirstConnexion'); ?></th>
             <th><?php echo get_lang('Time').' ';
-        Display:: display_icon(
+        Display::display_icon(
                     'info3.gif',
                     get_lang('TotalTimeByCourse'),
                     ['align' => 'absmiddle', 'hspace' => '3px']
                 ); ?></th>
             <th><?php echo get_lang('AverageScore').' ';
-        Display:: display_icon(
+        Display::display_icon(
                     'info3.gif',
                     get_lang('AverageIsCalculatedBasedInAllAttempts'),
                     ['align' => 'absmiddle', 'hspace' => '3px']
                 ); ?></th>
             <th><?php echo get_lang('LatestAttemptAverageScore').' ';
-        Display:: display_icon(
+        Display::display_icon(
                     'info3.gif',
                     get_lang('AverageIsCalculatedBasedInTheLatestAttempts'),
                     ['align' => 'absmiddle', 'hspace' => '3px']
                 ); ?></th>
             <th><?php echo get_lang('Progress').' ';
-        Display:: display_icon(
+        Display::display_icon(
                     'info3.gif',
                     get_lang('LPProgressScore'),
                     ['align' => 'absmiddle', 'hspace' => '3px']
                 ); ?></th>
             <th><?php echo get_lang('LastConnexion').' ';
-        Display:: display_icon(
+        Display::display_icon(
                     'info3.gif',
                     get_lang('LastTimeTheCourseWasUsed'),
                     ['align' => 'absmiddle', 'hspace' => '3px']
@@ -2031,7 +2031,7 @@ if (empty($_GET['details'])) {
         $rs2 = Database::query($sql2);
         $first_connection_date_to_module = Database::result($rs2, 0, 0);
         $i = 0;
-        while ($learnpath = Database:: fetch_array($rs_lp)) {
+        while ($learnpath = Database::fetch_array($rs_lp)) {
             $lp_id = intval($learnpath['id']);
             $lp_name = $learnpath['name'];
             $any_result = false;
@@ -2089,7 +2089,7 @@ if (empty($_GET['details'])) {
             );
 
             // Latest exercise results in a LP
-            $score_latest = Tracking:: get_avg_student_score(
+            $score_latest = Tracking::get_avg_student_score(
                 $studentId,
                 $course_code,
                 [$lp_id],
@@ -2192,7 +2192,7 @@ if (empty($_GET['details'])) {
         <tr>
             <th><?php echo get_lang('Exercises'); ?></th>
             <th><?php echo get_lang('LearningPath'); ?></th>
-            <th><?php echo get_lang('AvgCourseScore').' '.Display:: return_icon(
+            <th><?php echo get_lang('AvgCourseScore').' '.Display::return_icon(
                         'info3.gif',
                         get_lang('AverageScore'),
                         ['align' => 'absmiddle', 'hspace' => '3px']
@@ -2211,7 +2211,7 @@ if (empty($_GET['details'])) {
             get_lang('Attempts'),
         ];
 
-    $t_quiz = Database:: get_course_table(TABLE_QUIZ_TEST);
+    $t_quiz = Database::get_course_table(TABLE_QUIZ_TEST);
     $sql = "SELECT quiz.title, iid FROM $t_quiz AS quiz
                 WHERE
                     quiz.c_id = $c_id AND
@@ -2220,8 +2220,8 @@ if (empty($_GET['details'])) {
                 ORDER BY quiz.title ASC ";
     $result_exercices = Database::query($sql);
     $i = 0;
-    if (Database:: num_rows($result_exercices) > 0) {
-        while ($exercices = Database:: fetch_array($result_exercices)) {
+    if (Database::num_rows($result_exercices) > 0) {
+        while ($exercices = Database::fetch_array($result_exercices)) {
             $exercise_id = intval($exercices['iid']);
             $count_attempts = Tracking::count_student_exercise_attempts(
                     $studentId,
@@ -2294,8 +2294,8 @@ if (empty($_GET['details'])) {
                                             status          = ""
                                             ORDER BY exe_date DESC LIMIT 1';
             $result_last_attempt = Database::query($sql_last_attempt);
-            if (Database:: num_rows($result_last_attempt) > 0) {
-                $id_last_attempt = Database:: result($result_last_attempt, 0, 0);
+            if (Database::num_rows($result_last_attempt) > 0) {
+                $id_last_attempt = Database::result($result_last_attempt, 0, 0);
                 if ($count_attempts > 0) {
                     echo '<a href="../exercice/exercise_show.php?id='.$id_last_attempt.'&cidReq='.$course_code.'&session_id='.$session_id.'&student='.$studentId.'&origin='.(empty($_GET['origin']) ? 'tracking' : Security::remove_XSS(
                                 $_GET['origin']
@@ -2450,7 +2450,7 @@ if (empty($_GET['details'])) {
 
 if ($export_csv) {
     ob_end_clean();
-    Export:: export_table_csv($csv_content, 'reporting_student');
+    Export::export_table_csv($csv_content, 'reporting_student');
     exit;
 }
 ?>
@@ -2621,4 +2621,4 @@ echo '<a target="_blank"
     </tr>
 </table>
 
-<?php Display:: display_footer();
+<?php Display::display_footer();
diff --git a/main/extra/my_progress_ind.php b/main/extra/my_progress_ind.php
index f30d657889..337ed2e294 100644
--- a/main/extra/my_progress_ind.php
+++ b/main/extra/my_progress_ind.php
@@ -14,8 +14,8 @@ $nameTools = get_lang('MyProgress');
 $this_section = 'session_my_progress_ind';
 $_user = api_get_user_info();
 
-$tbl_stats_exercices = Database:: get_main_table(TABLE_STATISTIC_TRACK_E_EXERCISES);
-$tbl_stats_access = Database:: get_main_table(TABLE_STATISTIC_TRACK_E_ACCESS);
+$tbl_stats_exercices = Database::get_main_table(TABLE_STATISTIC_TRACK_E_EXERCISES);
+$tbl_stats_access = Database::get_main_table(TABLE_STATISTIC_TRACK_E_ACCESS);
 
 Display::display_header($nameTools);
 
@@ -126,7 +126,7 @@ while ($a_courses = Database::fetch_array($result2)) {
 api_display_tool_title($nameTools);
 
 $now = date('Y-m-d');
-$tbl_personal_agenda = Database:: get_main_table(TABLE_PERSONAL_AGENDA);
+$tbl_personal_agenda = Database::get_main_table(TABLE_PERSONAL_AGENDA);
 
 //on compte le nombre de m% dans l'agenda pour chaque module
 $sqljtot = "SELECT COUNT( * ) AS TOT
@@ -329,7 +329,7 @@ while ($a_courses = Database::fetch_array($result2)) {
     // The Tracking Class still uses the course code rather then the course id.
     $tracking_c_code = $course_code_id['code'];
     // time spent on the course
-    $time_spent_on_course = api_time_to_hms(Tracking:: get_time_spent_on_the_course($user_id, $c_id, $session_id));
+    $time_spent_on_course = api_time_to_hms(Tracking::get_time_spent_on_the_course($user_id, $c_id, $session_id));
     //  firts connection date
     $sql2 = "SELECT STR_TO_DATE(access_date,'%Y-%m-%d')
             FROM $tbl_stats_access
@@ -388,11 +388,11 @@ while ($a_courses = Database::fetch_array($result2)) {
     $end_date_module = $row[1];
     //fin de trouver la date de fin prévue du module
     //progression en %
-    $t_lp = Database:: get_course_table(TABLE_LP_MAIN);
+    $t_lp = Database::get_course_table(TABLE_LP_MAIN);
     $sql_lp = " SELECT lp.name, lp.id FROM $t_lp lp WHERE c_id = '$c_id'  ORDER BY lp.display_order";
     $rs_lp = Database::query($sql_lp);
     $i = 0;
-    while ($learnpath = Database:: fetch_array($rs_lp)) {
+    while ($learnpath = Database::fetch_array($rs_lp)) {
         $lp_id = intval($learnpath['id']);
         $lp_name = $learnpath['name'];
         $any_result = false;
diff --git a/main/extra/print_myStudents.php b/main/extra/print_myStudents.php
index 19a9d98fab..706a51ab78 100644
--- a/main/extra/print_myStudents.php
+++ b/main/extra/print_myStudents.php
@@ -18,10 +18,10 @@ if (isset($_GET['from']) && $_GET['from'] == 'myspace') {
 
 //$nameTools = get_lang('StudentDetails');
 $cidReset = true;
-$get_course_code = Security:: remove_XSS($_GET['course']);
+$get_course_code = Security::remove_XSS($_GET['course']);
 if (isset($_GET['details'])) {
     if (!empty($_GET['origin']) && $_GET['origin'] == 'user_course') {
-        $course_info = CourseManager:: get_course_information($get_course_code);
+        $course_info = CourseManager::get_course_information($get_course_code);
         if (empty($cidReq)) {
             $interbreadcrumb[] = [
                 "url" => api_get_path(WEB_COURSE_PATH).$course_info['directory'],
@@ -34,7 +34,7 @@ if (isset($_GET['details'])) {
         ];
     } else {
         if (!empty($_GET['origin']) && $_GET['origin'] == 'tracking_course') {
-            $course_info = CourseManager:: get_course_information($get_course_code);
+            $course_info = CourseManager::get_course_information($get_course_code);
             if (empty($cidReq)) {
                 //$interbreadcrumb[] = array ("url" => api_get_path(WEB_COURSE_PATH).$course_info['directory'], 'name' => $course_info['title']);
             }
@@ -53,7 +53,7 @@ if (isset($_GET['details'])) {
                     "name" => get_lang('SessionList'),
                 ];
                 $interbreadcrumb[] = [
-                    'url' => "../admin/resume_session.php?id_session=".Security:: remove_XSS($_GET['id_session']),
+                    'url' => "../admin/resume_session.php?id_session=".Security::remove_XSS($_GET['id_session']),
                     "name" => get_lang('SessionOverview'),
                 ];
             } else {
@@ -63,13 +63,13 @@ if (isset($_GET['details'])) {
                 ];
                 if (isset($_GET['id_coach']) && intval($_GET['id_coach']) != 0) {
                     $interbreadcrumb[] = [
-                        "url" => "student.php?id_coach=".Security:: remove_XSS($_GET['id_coach']),
+                        "url" => "student.php?id_coach=".Security::remove_XSS($_GET['id_coach']),
                         "name" => get_lang("CoachStudents"),
                     ];
                     $interbreadcrumb[] = [
-                        "url" => "myStudents.php?student=".Security:: remove_XSS(
+                        "url" => "myStudents.php?student=".Security::remove_XSS(
                                 $_GET['student']
-                            ).'&id_coach='.Security:: remove_XSS($_GET['id_coach']),
+                            ).'&id_coach='.Security::remove_XSS($_GET['id_coach']),
                         "name" => get_lang("StudentDetails"),
                     ];
                 } else {
@@ -78,7 +78,7 @@ if (isset($_GET['details'])) {
                         "name" => get_lang("MyStudents"),
                     ];
                     $interbreadcrumb[] = [
-                        "url" => "myStudents.php?student=".Security:: remove_XSS($_GET['student']),
+                        "url" => "myStudents.php?student=".Security::remove_XSS($_GET['student']),
                         "name" => get_lang("StudentDetails"),
                     ];
                 }
@@ -97,7 +97,7 @@ if (isset($_GET['details'])) {
             "name" => get_lang('SessionList'),
         ];
         $interbreadcrumb[] = [
-            'url' => "../admin/resume_session.php?id_session=".Security:: remove_XSS($_GET['id_session']),
+            'url' => "../admin/resume_session.php?id_session=".Security::remove_XSS($_GET['id_session']),
             "name" => get_lang('SessionOverview'),
         ];
     } else {
@@ -108,14 +108,14 @@ if (isset($_GET['details'])) {
         if (isset($_GET['id_coach']) && intval($_GET['id_coach']) != 0) {
             if (isset($_GET['id_session']) && intval($_GET['id_session']) != 0) {
                 $interbreadcrumb[] = [
-                    "url" => "student.php?id_coach=".Security:: remove_XSS(
+                    "url" => "student.php?id_coach=".Security::remove_XSS(
                             $_GET['id_coach']
                         )."&id_session=".$_GET['id_session'],
                     "name" => get_lang("CoachStudents"),
                 ];
             } else {
                 $interbreadcrumb[] = [
-                    "url" => "student.php?id_coach=".Security:: remove_XSS($_GET['id_coach']),
+                    "url" => "student.php?id_coach=".Security::remove_XSS($_GET['id_coach']),
                     "name" => get_lang("CoachStudents"),
                 ];
             }
@@ -135,8 +135,8 @@ if (!api_is_allowed_to_edit() && !api_is_coach() && !api_is_drh() && !api_is_cou
     api_not_allowed(true);
 }
 
-Display:: display_header($nameTools);
-$tbl_stats_exercices = Database:: get_main_table(TABLE_STATISTIC_TRACK_E_EXERCISES);
+Display::display_header($nameTools);
+$tbl_stats_exercices = Database::get_main_table(TABLE_STATISTIC_TRACK_E_EXERCISES);
 
 if (isset($_GET['user_id']) && $_GET['user_id'] != '') {
     $user_id = intval($_GET['user_id']);
diff --git a/main/extra/userInfo.php b/main/extra/userInfo.php
index 38b59c9924..33b6ee5275 100644
--- a/main/extra/userInfo.php
+++ b/main/extra/userInfo.php
@@ -9,7 +9,7 @@ if (empty($allow)) {
     exit;
 }
 
-$TABLECALHORAIRE = Database :: get_course_table(cal_horaire);
+$TABLECALHORAIRE = Database::get_course_table(cal_horaire);
 $htmlHeadXtra[] = '<script>
 function show_image(image,width,height) {
 	width = parseInt(width) + 20;
@@ -31,15 +31,15 @@ if (api_is_anonymous()) {
 }
 
 //prepare variables used in userInfoLib.php functions
-$TBL_USERINFO_DEF = Database:: get_course_table(TABLE_USER_INFO_DEF);
-$TBL_USERINFO_CONTENT = Database:: get_course_table(TABLE_USER_INFO_CONTENT);
+$TBL_USERINFO_DEF = Database::get_course_table(TABLE_USER_INFO_DEF);
+$TBL_USERINFO_CONTENT = Database::get_course_table(TABLE_USER_INFO_CONTENT);
 
 if ($tool_info['visibility'] == 1) {
     $interbreadcrumb[] = ['url' => 'user.php', 'name' => get_lang('Users')];
 }
 
 if ($origin != 'learnpath') { //so we are not in learnpath tool
-    Display :: display_header($nameTools, "User");
+    Display::display_header($nameTools, "User");
     $origin = Security::remove_XSS($_GET['origin']);
 } else {
     ?> <link rel="stylesheet" type="text/css" href="<?php echo api_get_path(WEB_CODE_PATH); ?>css/default.css" /> <?php
@@ -309,7 +309,7 @@ if ($displayMode == "viewDefEdit") {
         }
         echo "<td><button class=\"save\" type=\"submit\" name=\"submit\">".get_lang('SaveChanges')."</button></td>\n", "</tr>", "</table>", "</form>\n";
         if (api_get_setting('show_email_addresses') == 'true') {
-            echo "<p>".Display:: encrypted_mailto_link($mainUserInfo['email'], $mainUserInfo['email'])."</p>";
+            echo "<p>".Display::encrypted_mailto_link($mainUserInfo['email'], $mainUserInfo['email'])."</p>";
         }
 
         if (api_get_setting('extended_profile') == 'true') {
diff --git a/main/extra/userInfoLib.php b/main/extra/userInfoLib.php
index e972fb8de6..20e28fd8e4 100644
--- a/main/extra/userInfoLib.php
+++ b/main/extra/userInfoLib.php
@@ -96,8 +96,8 @@ function edit_cat_def($id, $title, $comment, $nbline)
  */
 function remove_cat_def($id, $force = false)
 {
-    $TBL_USERINFO_DEF = Database:: get_course_table(TABLE_USER_INFO_DEF);
-    $TBL_USERINFO_CONTENT = Database:: get_course_table(TABLE_USER_INFO_CONTENT);
+    $TBL_USERINFO_DEF = Database::get_course_table(TABLE_USER_INFO_DEF);
+    $TBL_USERINFO_CONTENT = Database::get_course_table(TABLE_USER_INFO_CONTENT);
 
     $id = strval(intval($id));
 
@@ -132,7 +132,7 @@ function remove_cat_def($id, $force = false)
  */
 function move_cat_rank($id, $direction) // up & down.
 {
-    $TBL_USERINFO_DEF = Database:: get_course_table(userinfo_def);
+    $TBL_USERINFO_DEF = Database::get_course_table(userinfo_def);
     $id = strval(intval($id));
 
     if (0 == (int) $id || !($direction == "up" || $direction == "down")) {
@@ -167,7 +167,7 @@ function move_cat_rank($id, $direction) // up & down.
  */
 function move_cat_rank_by_rank($rank, $direction) // up & down.
 {
-    $TBL_USERINFO_DEF = Database:: get_course_table(userinfo_def);
+    $TBL_USERINFO_DEF = Database::get_course_table(userinfo_def);
 
     if (0 == (int) $rank || !($direction == "up" || $direction == "down")) {
         return false;
@@ -243,8 +243,8 @@ function update_user_course_properties($user_id, $course_code, $properties, $hor
              WHERE user_id = $user_id";
     Database::query($sql2);
     //on récupère l'horaire
-    $tbl_personal_agenda = Database:: get_main_table(TABLE_PERSONAL_AGENDA);
-    $TABLECALDATES = Database:: get_course_table(cal_dates);
+    $tbl_personal_agenda = Database::get_main_table(TABLE_PERSONAL_AGENDA);
+    $TABLECALDATES = Database::get_course_table(cal_dates);
     $jour = 0;
     $sql3 = "SELECT date FROM $TABLECALDATES
              WHERE
@@ -435,8 +435,8 @@ function cleanout_cat_content($user_id, $definition_id)
  */
 function get_course_user_info($user_id)
 {
-    $TBL_USERINFO_DEF = Database:: get_course_table(TABLE_USER_INFO_DEF);
-    $TBL_USERINFO_CONTENT = Database:: get_course_table(TABLE_USER_INFO_CONTENT);
+    $TBL_USERINFO_DEF = Database::get_course_table(TABLE_USER_INFO_DEF);
+    $TBL_USERINFO_CONTENT = Database::get_course_table(TABLE_USER_INFO_CONTENT);
 
     $user_id = (int) $user_id;
     $sql = "SELECT  cat.id catId,   cat.title,
@@ -471,8 +471,8 @@ function get_course_user_info($user_id)
  */
 function get_cat_content($userId, $catId)
 {
-    $TBL_USERINFO_DEF = Database:: get_course_table(TABLE_USER_INFO_DEF);
-    $TBL_USERINFO_CONTENT = Database:: get_course_table(TABLE_USER_INFO_CONTENT);
+    $TBL_USERINFO_DEF = Database::get_course_table(TABLE_USER_INFO_DEF);
+    $TBL_USERINFO_CONTENT = Database::get_course_table(TABLE_USER_INFO_CONTENT);
 
     $userId = (int) $userId;
     $catId = (int) $catId;
@@ -507,7 +507,7 @@ function get_cat_content($userId, $catId)
  */
 function get_cat_def($catId)
 {
-    $TBL_USERINFO_DEF = Database:: get_course_table(TABLE_USER_INFO_DEF);
+    $TBL_USERINFO_DEF = Database::get_course_table(TABLE_USER_INFO_DEF);
 
     $catId = (int) $catId;
     $sql = "SELECT id, title, comment, line_count, rank FROM $TBL_USERINFO_DEF WHERE id = $catId";
@@ -536,7 +536,7 @@ function get_cat_def($catId)
  */
 function get_cat_def_list()
 {
-    $TBL_USERINFO_DEF = Database:: get_course_table(TABLE_USER_INFO_DEF);
+    $TBL_USERINFO_DEF = Database::get_course_table(TABLE_USER_INFO_DEF);
 
     $sql = "SELECT  id catId,   title,  comment , line_count
             FROM  $TBL_USERINFO_DEF
diff --git a/main/forum/editthread.php b/main/forum/editthread.php
index 9aee29dde1..a4516e6bcd 100644
--- a/main/forum/editthread.php
+++ b/main/forum/editthread.php
@@ -89,7 +89,7 @@ if (api_is_invitee()) {
 
 $groupId = api_get_group_id();
 if (!empty($groupId)) {
-    $groupProperties = GroupManager:: get_group_properties($groupId);
+    $groupProperties = GroupManager::get_group_properties($groupId);
     $interbreadcrumb[] = [
         'url' => api_get_path(WEB_CODE_PATH).'group/group.php?'.$cidreq,
         'name' => get_lang('Groups'),
diff --git a/main/forum/forumqualify.php b/main/forum/forumqualify.php
index c13b668285..4d92beae9d 100755
--- a/main/forum/forumqualify.php
+++ b/main/forum/forumqualify.php
@@ -338,5 +338,5 @@ if (api_is_allowed_to_edit() && $counter > 0) {
 }
 
 if ($origin != 'learnpath') {
-    Display:: display_footer();
+    Display::display_footer();
 }
diff --git a/main/forum/forumsearch.php b/main/forum/forumsearch.php
index b19b21b384..ec3a6187b8 100755
--- a/main/forum/forumsearch.php
+++ b/main/forum/forumsearch.php
@@ -46,7 +46,7 @@ if (api_is_in_gradebook()) {
 $groupId = api_get_group_id();
 
 if ($origin == 'group') {
-    $group_properties = GroupManager:: get_group_properties($groupId);
+    $group_properties = GroupManager::get_group_properties($groupId);
     $interbreadcrumb[] = [
         'url' => api_get_path(WEB_CODE_PATH).'group/group.php?'.api_get_cidreq(),
         'name' => get_lang('Groups'),
@@ -89,5 +89,5 @@ forum_search();
 
 // Footer
 if ('learnpath' != $origin) {
-    Display :: display_footer();
+    Display::display_footer();
 }
diff --git a/main/gradebook/gradebook.php b/main/gradebook/gradebook.php
index a8659e9d9a..862a66ec0e 100755
--- a/main/gradebook/gradebook.php
+++ b/main/gradebook/gradebook.php
@@ -45,7 +45,7 @@ $filter_warning_msg = true;
 //this is called when there is no data for the course admin
 if (isset($_GET['createallcategories'])) {
     GradebookUtils::block_students();
-    $coursecat = Category :: get_not_created_course_categories(api_get_user_id());
+    $coursecat = Category::get_not_created_course_categories(api_get_user_id());
     if (!count($coursecat) == 0) {
         foreach ($coursecat as $row) {
             $cat = new Category();
@@ -68,7 +68,7 @@ if (isset($_GET['createallcategories'])) {
 if (isset($_GET['movecat'])) {
     $move_cat = (int) $_GET['movecat'];
     GradebookUtils::block_students();
-    $cats = Category :: load($move_cat);
+    $cats = Category::load($move_cat);
     if (!isset($_GET['targetcat'])) {
         $move_form = new CatForm(
             CatForm::TYPE_MOVE,
@@ -85,7 +85,7 @@ if (isset($_GET['movecat'])) {
         }
     } else {
         $get_target_cat = Security::remove_XSS($_GET['targetcat']);
-        $targetcat = Category :: load($get_target_cat);
+        $targetcat = Category::load($get_target_cat);
         $course_to_crsind = ($cats[0]->get_course_code() != null && $targetcat[0]->get_course_code() == null);
 
         if (!($course_to_crsind && !isset($_GET['confirm']))) {
@@ -102,7 +102,7 @@ if (isset($_GET['movecat'])) {
 if (isset($_GET['moveeval'])) {
     GradebookUtils::block_students();
     $get_move_eval = Security::remove_XSS($_GET['moveeval']);
-    $evals = Evaluation :: load($get_move_eval);
+    $evals = Evaluation::load($get_move_eval);
     if (!isset($_GET['targetcat'])) {
         $move_form = new EvalForm(
             EvalForm::TYPE_MOVE,
@@ -121,7 +121,7 @@ if (isset($_GET['moveeval'])) {
         }
     } else {
         $get_target_cat = Security::remove_XSS($_GET['targetcat']);
-        $targetcat = Category :: load($get_target_cat);
+        $targetcat = Category::load($get_target_cat);
         $course_to_crsind = ($evals[0]->get_course_code() != null && $targetcat[0]->get_course_code() == null);
 
         if (!($course_to_crsind && !isset($_GET['confirm']))) {
@@ -148,7 +148,7 @@ if (isset($_GET['movelink'])) {
         api_get_self().'?movelink='.$get_move_link.'&selectcat='.$selectcat
     );
     if ($move_form->validate()) {
-        $targetcat = Category :: load($move_form->exportValue('move_cat'));
+        $targetcat = Category::load($move_form->exportValue('move_cat'));
         $link[0]->move_to_cat($targetcat[0]);
         unset($link);
         header('Location: '.api_get_self().'?linkmoved=&selectcat='.$selectcat);
@@ -164,7 +164,7 @@ if (isset($_GET['visiblecat'])) {
     } else {
         $visibility_command = 0;
     }
-    $cats = Category :: load($_GET['visiblecat']);
+    $cats = Category::load($_GET['visiblecat']);
     $cats[0]->set_visible($visibility_command);
     $cats[0]->save();
     $cats[0]->apply_visibility_to_children();
@@ -179,7 +179,7 @@ if (isset($_GET['visiblecat'])) {
 }
 if (isset($_GET['deletecat'])) {
     GradebookUtils::block_students();
-    $cats = Category :: load($_GET['deletecat']);
+    $cats = Category::load($_GET['deletecat']);
     //delete all categories,subcategories and results
     if ($cats[0] != null) {
         if ($cats[0]->get_id() != 0) {
@@ -200,7 +200,7 @@ if (isset($_GET['visibleeval'])) {
         $visibility_command = 0;
     }
 
-    $eval = Evaluation :: load($_GET['visibleeval']);
+    $eval = Evaluation::load($_GET['visibleeval']);
     $eval[0]->set_visible($visibility_command);
     $eval[0]->save();
     unset($eval);
@@ -215,7 +215,7 @@ if (isset($_GET['visibleeval'])) {
 
 if (isset($_GET['deleteeval'])) {
     GradebookUtils::block_students();
-    $eval = Evaluation :: load($_GET['deleteeval']);
+    $eval = Evaluation::load($_GET['deleteeval']);
     if ($eval[0] != null) {
         $eval[0]->delete_with_results();
     }
@@ -230,7 +230,7 @@ if (isset($_GET['visiblelink'])) {
     } else {
         $visibility_command = 0;
     }
-    $link = LinkFactory :: load($_GET['visiblelink']);
+    $link = LinkFactory::load($_GET['visiblelink']);
     $link[0]->set_visible($visibility_command);
     $link[0]->save();
     unset($link);
@@ -246,7 +246,7 @@ if (isset($_GET['deletelink'])) {
     GradebookUtils::block_students();
     //fixing #5229
     if (!empty($_GET['deletelink'])) {
-        $link = LinkFactory:: load($_GET['deletelink']);
+        $link = LinkFactory::load($_GET['deletelink']);
         if ($link[0] != null) {
             $link[0]->delete();
         }
@@ -288,14 +288,14 @@ if (isset($_POST['action'])) {
                 $number_of_deleted_links = 0;
                 foreach ($_POST['id'] as $indexstr) {
                     if (api_substr($indexstr, 0, 4) == 'CATE') {
-                        $cats = Category :: load(api_substr($indexstr, 4));
+                        $cats = Category::load(api_substr($indexstr, 4));
                         if ($cats[0] != null) {
                             $cats[0]->delete_all();
                         }
                         $number_of_deleted_categories++;
                     }
                     if (api_substr($indexstr, 0, 4) == 'EVAL') {
-                        $eval = Evaluation :: load(api_substr($indexstr, 4));
+                        $eval = Evaluation::load(api_substr($indexstr, 4));
                         if ($eval[0] != null) {
                             $eval[0]->delete_with_results();
                         }
@@ -304,7 +304,7 @@ if (isset($_POST['action'])) {
                     if (api_substr($indexstr, 0, 4) == 'LINK') {
                         $id = api_substr($indexstr, 4);
                         if (!empty($id)) {
-                            $link = LinkFactory :: load();
+                            $link = LinkFactory::load();
                             if ($link[0] != null) {
                                 $link[0]->delete();
                             }
@@ -318,18 +318,18 @@ if (isset($_POST['action'])) {
             case 'setvisible':
                 foreach ($_POST['id'] as $indexstr) {
                     if (api_substr($indexstr, 0, 4) == 'CATE') {
-                        $cats = Category:: load(api_substr($indexstr, 4));
+                        $cats = Category::load(api_substr($indexstr, 4));
                         $cats[0]->set_visible(1);
                         $cats[0]->save();
                         $cats[0]->apply_visibility_to_children();
                     }
                     if (api_substr($indexstr, 0, 4) == 'EVAL') {
-                        $eval = Evaluation:: load(api_substr($indexstr, 4));
+                        $eval = Evaluation::load(api_substr($indexstr, 4));
                         $eval[0]->set_visible(1);
                         $eval[0]->save();
                     }
                     if (api_substr($indexstr, 0, 4) == 'LINK') {
-                        $link = LinkFactory:: load(api_substr($indexstr, 4));
+                        $link = LinkFactory::load(api_substr($indexstr, 4));
                         $link[0]->set_visible(1);
                         $link[0]->save();
                     }
@@ -340,18 +340,18 @@ if (isset($_POST['action'])) {
             case 'setinvisible':
                 foreach ($_POST['id'] as $indexstr) {
                     if (api_substr($indexstr, 0, 4) == 'CATE') {
-                        $cats = Category:: load(api_substr($indexstr, 4));
+                        $cats = Category::load(api_substr($indexstr, 4));
                         $cats[0]->set_visible(0);
                         $cats[0]->save();
                         $cats[0]->apply_visibility_to_children();
                     }
                     if (api_substr($indexstr, 0, 4) == 'EVAL') {
-                        $eval = Evaluation:: load(api_substr($indexstr, 4));
+                        $eval = Evaluation::load(api_substr($indexstr, 4));
                         $eval[0]->set_visible(0);
                         $eval[0]->save();
                     }
                     if (api_substr($indexstr, 0, 4) == 'LINK') {
-                        $link = LinkFactory:: load(api_substr($indexstr, 4));
+                        $link = LinkFactory::load(api_substr($indexstr, 4));
                         $link[0]->set_visible(0);
                         $link[0]->save();
                     }
@@ -419,7 +419,7 @@ if (!isset($_GET['exportpdf']) && !isset($_GET['export_certificate'])) {
             'url' => Category::getUrl().'selectcat='.$selectcat,
             'name' => get_lang('ToolGradebook'),
         ];
-        Display :: display_header(get_lang('FlatView'));
+        Display::display_header(get_lang('FlatView'));
     } elseif (isset($_GET['search'])) {
         $interbreadcrumb[] = [
             'url' => Category::getUrl(),
@@ -439,9 +439,9 @@ if (!isset($_GET['exportpdf']) && !isset($_GET['export_certificate'])) {
                 ];
             }
         }
-        Display :: display_header('');
+        Display::display_header('');
     } else {
-        Display :: display_header('');
+        Display::display_header('');
     }
 }
 
@@ -458,7 +458,7 @@ if (empty($selectcat)) {
 // search form
 
 $simple_search_form = new UserForm(
-    UserForm :: TYPE_SIMPLE_SEARCH,
+    UserForm::TYPE_SIMPLE_SEARCH,
     null,
     'simple_search_form',
     null,
@@ -474,7 +474,7 @@ if ($simple_search_form->validate() && (empty($keyword))) {
 }
 
 if (!empty($keyword)) {
-    $cats = Category :: load($category);
+    $cats = Category::load($category);
     $allcat = [];
     if ((isset($_GET['selectcat']) && $_GET['selectcat'] == 0) && isset($_GET['search'])) {
         $allcat = $cats[0]->get_subcategories(null);
@@ -487,7 +487,7 @@ if (!empty($keyword)) {
     }
 } elseif (isset($_GET['studentoverview'])) {
     //@todo this code seems to be deprecated because the gradebook tab is off
-    $cats = Category :: load($category);
+    $cats = Category::load($category);
     $stud_id = (api_is_allowed_to_edit() ? null : api_get_user_id());
     $allcat = [];
     $alleval = $cats[0]->get_evaluations($stud_id, true);
@@ -501,7 +501,7 @@ if (!empty($keyword)) {
             get_lang('Date'),
             get_lang('Results'),
         ];
-        $data_array = $datagen->get_data(GradebookDataGenerator :: GDG_SORT_NAME, 0, null, true);
+        $data_array = $datagen->get_data(GradebookDataGenerator::GDG_SORT_NAME, 0, null, true);
         $newarray = [];
         foreach ($data_array as $data) {
             $newarray[] = array_slice($data, 1);
@@ -535,14 +535,14 @@ if (!empty($keyword)) {
     if (!api_is_allowed_to_edit(true, true)) {
         $user_id = api_get_user_id();
     }
-    $category = Category :: load($_GET['cat_id']);
+    $category = Category::load($_GET['cat_id']);
     if ($category[0]->is_certificate_available($user_id)) {
         $user = api_get_user_info($user_id);
-        $scoredisplay = ScoreDisplay :: instance();
+        $scoredisplay = ScoreDisplay::instance();
         $scorecourse = $category[0]->calc_score($user_id);
         $scorecourse_display = (isset($scorecourse) ? $scoredisplay->display_score($scorecourse, SCORE_AVERAGE) : get_lang('NoResultsAvailable'));
 
-        $cattotal = Category :: load(0);
+        $cattotal = Category::load(0);
         $scoretotal = $cattotal[0]->calc_score($user_id);
         $scoretotal_display = (isset($scoretotal) ? $scoredisplay->display_score($scoretotal, SCORE_PERCENT) : get_lang('NoResultsAvailable'));
 
@@ -575,7 +575,7 @@ if (!empty($keyword)) {
     }
     exit;
 } else {
-    $cats = Category :: load($category);
+    $cats = Category::load($category);
     $stud_id = (api_is_allowed_to_edit() ? null : api_get_user_id());
     $allcat = $cats[0]->get_subcategories($stud_id);
     $alleval = $cats[0]->get_evaluations($stud_id);
@@ -618,7 +618,7 @@ if (empty($allcat) && empty($alleval) && empty($alllink) &&
 }
 // Here we are in a sub category
 if ($category != '0') {
-    DisplayGradebook:: header(
+    DisplayGradebook::header(
         $cats[0],
         1,
         $_GET['selectcat'],
@@ -628,7 +628,7 @@ if ($category != '0') {
     );
 } else {
     // This is the root category
-    DisplayGradebook:: header(
+    DisplayGradebook::header(
         $cats[0],
         count($allcat) == '0' && !isset($_GET['search']) ? 0 : 1,
         0,
@@ -638,4 +638,4 @@ if ($category != '0') {
     );
 }
 $gradebooktable->display();
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/gradebook/gradebook_add_cat.php b/main/gradebook/gradebook_add_cat.php
index 018f3acd35..21a8ff48c6 100755
--- a/main/gradebook/gradebook_add_cat.php
+++ b/main/gradebook/gradebook_add_cat.php
@@ -18,7 +18,7 @@ $catadd = new Category();
 $my_user_id = api_get_user_id();
 $catadd->set_user_id($my_user_id);
 $catadd->set_parent_id($get_select_cat);
-$catcourse = Category :: load($get_select_cat);
+$catcourse = Category::load($get_select_cat);
 
 if ($_in_course) {
     $catadd->set_course_code($course_code);
@@ -114,11 +114,11 @@ if (!$_in_course) {
     ];
 }
 $interbreadcrumb[] = ['url' => 'index.php?'.api_get_cidreq(), 'name' => get_lang('ToolGradebook')];
-Display :: display_header(get_lang('NewCategory'));
+Display::display_header(get_lang('NewCategory'));
 
 $display_form = true;
 if ($display_form) {
     $form->display();
 }
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/gradebook/gradebook_add_eval.php b/main/gradebook/gradebook_add_eval.php
index 549e24fa7b..f48611c621 100755
--- a/main/gradebook/gradebook_add_eval.php
+++ b/main/gradebook/gradebook_add_eval.php
@@ -132,4 +132,4 @@ if ($evaladd->get_course_code() == null) {
 Display::display_header(get_lang('NewEvaluation'));
 
 $form->display();
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/gradebook/gradebook_add_link_select_course.php b/main/gradebook/gradebook_add_link_select_course.php
index 699fd7d2ac..01ab9b3da3 100755
--- a/main/gradebook/gradebook_add_link_select_course.php
+++ b/main/gradebook/gradebook_add_link_select_course.php
@@ -13,9 +13,9 @@ $selectCat = isset($_GET['selectcat']) ? (int) $_GET['selectcat'] : 0;
 $catadd = new Category();
 $catadd->set_user_id(api_get_user_id());
 $catadd->set_parent_id($selectCat);
-$catcourse = Category :: load($selectCat);
+$catcourse = Category::load($selectCat);
 $form = new CatForm(
-    CatForm :: TYPE_SELECT_COURSE,
+    CatForm::TYPE_SELECT_COURSE,
     $catadd,
     'add_cat_form',
     null,
@@ -35,6 +35,6 @@ $interbreadcrumb[] = [
     'url' => Category::getUrl().'selectcat='.$selectCat,
     'name' => get_lang('Gradebook'),
 ];
-Display :: display_header(get_lang('NewCategory'));
+Display::display_header(get_lang('NewCategory'));
 $form->display();
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/gradebook/gradebook_add_result.php b/main/gradebook/gradebook_add_result.php
index 97863ccbd8..9c84e1d201 100755
--- a/main/gradebook/gradebook_add_result.php
+++ b/main/gradebook/gradebook_add_result.php
@@ -59,7 +59,7 @@ $interbreadcrumb[] = [
     'url' => Category::getUrl(),
     'name' => get_lang('Gradebook'),
 ];
-Display :: display_header(get_lang('AddResult'));
+Display::display_header(get_lang('AddResult'));
 DisplayGradebook::display_header_result($evaluation[0], null, 0, 0);
 echo $table;
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/gradebook/gradebook_add_user.php b/main/gradebook/gradebook_add_user.php
index 10e0069c53..3cf8b53734 100755
--- a/main/gradebook/gradebook_add_user.php
+++ b/main/gradebook/gradebook_add_user.php
@@ -71,12 +71,12 @@ $interbreadcrumb[] = [
     'url' => 'gradebook_view_result.php?selecteval='.Security::remove_XSS($_GET['selecteval']).'&'.api_get_cidreq(),
     'name' => get_lang('ViewResult'),
 ];
-Display :: display_header(get_lang('AddUserToEval'));
+Display::display_header(get_lang('AddUserToEval'));
 if (isset($_GET['erroroneuser'])) {
     echo Display::return_message(get_lang('AtLeastOneUser'), 'warning', false);
 }
-DisplayGradebook :: display_header_result($evaluation[0], null, 0, 0);
+DisplayGradebook::display_header_result($evaluation[0], null, 0, 0);
 echo '<div class="main">';
 echo $add_user_form->toHtml();
 echo '</div>';
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/gradebook/gradebook_edit_all.php b/main/gradebook/gradebook_edit_all.php
index c9a6c4e5b0..d1507cae7f 100755
--- a/main/gradebook/gradebook_edit_all.php
+++ b/main/gradebook/gradebook_edit_all.php
@@ -247,13 +247,13 @@ if (!isset($_GET['exportpdf']) && !isset($_GET['export_certificate'])) {
             'url' => Category::getUrl().'selectcat='.$my_selectcat,
             'name' => get_lang('Gradebook'),
         ];
-        Display:: display_header(get_lang('FlatView'));
+        Display::display_header(get_lang('FlatView'));
     } elseif (isset($_GET['search'])) {
         $interbreadcrumb[] = [
             'url' => Category::getUrl().'selectcat='.$my_selectcat,
             'name' => get_lang('Gradebook'),
         ];
-        Display:: display_header(get_lang('SearchResults'));
+        Display::display_header(get_lang('SearchResults'));
     } else {
         $interbreadcrumb[] = [
             'url' => Category::getUrl().'selectcat=1',
@@ -263,7 +263,7 @@ if (!isset($_GET['exportpdf']) && !isset($_GET['export_certificate'])) {
             'url' => '#',
             'name' => get_lang('EditAllWeights'),
         ];
-        Display:: display_header('');
+        Display::display_header('');
     }
 }
 ?>
@@ -309,4 +309,4 @@ echo Display::return_message(sprintf(get_lang('TotalWeightMustBeX'), $original_t
     </button>
 </form>
 <?php
-Display:: display_footer();
+Display::display_footer();
diff --git a/main/gradebook/gradebook_edit_eval.php b/main/gradebook/gradebook_edit_eval.php
index fb0d312037..9873b57b3a 100755
--- a/main/gradebook/gradebook_edit_eval.php
+++ b/main/gradebook/gradebook_edit_eval.php
@@ -31,7 +31,7 @@ if ($form->validate()) {
     $eval->set_course_code($values['hid_course_code']);
     $eval->set_category_id($values['hid_category_id']);
 
-    $parent_cat = Category :: load($values['hid_category_id']);
+    $parent_cat = Category::load($values['hid_category_id']);
     $final_weight = $values['weight_mask'];
 
     $eval->set_weight($final_weight);
diff --git a/main/gradebook/gradebook_edit_link.php b/main/gradebook/gradebook_edit_link.php
index fb74dee9fe..27026000e1 100755
--- a/main/gradebook/gradebook_edit_link.php
+++ b/main/gradebook/gradebook_edit_link.php
@@ -17,7 +17,7 @@ $tbl_forum_thread = Database::get_course_table(TABLE_FORUM_THREAD);
 $tbl_attendance = Database::get_course_table(TABLE_ATTENDANCE);
 $em = Database::getManager();
 
-$linkarray = LinkFactory :: load($_GET['editlink']);
+$linkarray = LinkFactory::load($_GET['editlink']);
 /** @var AbstractLink $link */
 $link = $linkarray[0];
 if ($link->is_locked() && !api_is_platform_admin()) {
@@ -30,7 +30,7 @@ $course_code = api_get_course_id();
 $session_id = api_get_session_id();
 
 if ($session_id == 0) {
-    $cats = Category:: load(
+    $cats = Category::load(
         null,
         null,
         $course_code,
@@ -53,7 +53,7 @@ $form = new LinkAddEditForm(
 );
 if ($form->validate()) {
     $values = $form->exportValues();
-    $parent_cat = Category :: load($values['select_gradebook']);
+    $parent_cat = Category::load($values['select_gradebook']);
     $final_weight = $values['weight_mask'];
     $link->set_weight($final_weight);
 
@@ -142,6 +142,6 @@ $(function() {
 });
 </script>';
 
-Display :: display_header(get_lang('EditLink'));
+Display::display_header(get_lang('EditLink'));
 $form->display();
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/gradebook/gradebook_edit_result.php b/main/gradebook/gradebook_edit_result.php
index af6259a250..be761efef0 100755
--- a/main/gradebook/gradebook_edit_result.php
+++ b/main/gradebook/gradebook_edit_result.php
@@ -84,4 +84,4 @@ $interbreadcrumb[] = [
 Display::display_header(get_lang('EditResult'));
 DisplayGradebook::display_header_result($evaluation[0], null, 0, 0);
 echo $table;
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/gradebook/gradebook_showlog_eval.php b/main/gradebook/gradebook_showlog_eval.php
index 9f724c99d3..794b937cad 100755
--- a/main/gradebook/gradebook_showlog_eval.php
+++ b/main/gradebook/gradebook_showlog_eval.php
@@ -31,7 +31,7 @@ $t_linkeval_log = Database::get_main_table(TABLE_MAIN_GRADEBOOK_LINKEVAL_LOG);
 $t_user = Database::get_main_table(TABLE_MAIN_USER);
 $visible_log = Security::remove_XSS($_GET['visiblelog']);
 
-$evaledit = Evaluation :: load($visible_log);
+$evaledit = Evaluation::load($visible_log);
 $sql = "SELECT le.name,le.description,le.weight,le.visible,le.type,le.created_at, us.user_id
         FROM $t_linkeval_log le
         INNER JOIN $t_user us
@@ -73,4 +73,4 @@ $table->set_header(5, get_lang('Date'));
 $table->set_header(6, get_lang('GradebookWhoChangedItLog'));
 
 $table->display();
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/gradebook/gradebook_showlog_link.php b/main/gradebook/gradebook_showlog_link.php
index d9fd523c73..271783fd9b 100755
--- a/main/gradebook/gradebook_showlog_link.php
+++ b/main/gradebook/gradebook_showlog_link.php
@@ -34,7 +34,7 @@ echo '</div>';
 $t_user = Database::get_main_table(TABLE_MAIN_USER);
 $t_link_log = Database::get_main_table(TABLE_MAIN_GRADEBOOK_LINKEVAL_LOG);
 $visible_link = Security::remove_XSS($_GET['visiblelink']);
-$evaledit = EvalLink:: load($visible_link);
+$evaledit = EvalLink::load($visible_link);
 $sql = "SELECT lk.name,lk.description,lk.weight,lk.visible,lk.type,lk.created_at,us.username
         FROM ".$t_link_log." lk inner join ".$t_user." us
         ON lk.user_id_log=us.user_id
@@ -66,4 +66,4 @@ $table->set_header(5, get_lang('Date'));
 $table->set_header(6, get_lang('GradebookWhoChangedItLog'));
 $table->display();
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/gradebook/gradebook_statistics.php b/main/gradebook/gradebook_statistics.php
index faeabe4ed8..7e57be36fe 100755
--- a/main/gradebook/gradebook_statistics.php
+++ b/main/gradebook/gradebook_statistics.php
@@ -106,4 +106,4 @@ if (!$displayScore->is_custom() || empty($displays)) {
     $html .= '</table>';
     echo $html;
 }
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/gradebook/gradebook_view_result.php b/main/gradebook/gradebook_view_result.php
index ea516ee6cf..d5fd7afa1e 100755
--- a/main/gradebook/gradebook_view_result.php
+++ b/main/gradebook/gradebook_view_result.php
@@ -46,7 +46,7 @@ if (isset($_GET['delete_mark'])) {
 }
 
 if (isset($_GET['selecteval'])) {
-    $allresults = Result :: load(null, null, $select_eval);
+    $allresults = Result::load(null, null, $select_eval);
     $iscourse = !empty(api_get_course_id());
 }
 
@@ -222,7 +222,7 @@ if (isset($_GET['import'])) {
         ''
     );
     if (!$import_result_form->validate()) {
-        Display :: display_header(get_lang('Import'));
+        Display::display_header(get_lang('Import'));
     }
     $eval[0]->check_lock_permissions();
     if (isset($_POST['formSent']) && $_POST['formSent']) {
@@ -230,7 +230,7 @@ if (isset($_GET['import'])) {
             $values = $import_result_form->exportValues();
             $file_type = $_POST['file_type'];
             $file_name = $_FILES['import_file']['tmp_name'];
-            $results = Import :: csvToArray($file_name);
+            $results = Import::csvToArray($file_name);
             $nr_results_added = 0;
             foreach ($results as $index => $importedresult) {
                 //check username & score
@@ -415,7 +415,7 @@ if (isset($_GET['export'])) {
                 $head_table[] = [get_lang('Letters'), 15];
             }
             $head_display_score = '';
-            $scoredisplay = ScoreDisplay :: instance();
+            $scoredisplay = ScoreDisplay::instance();
             $customdisplays = $scoredisplay->get_custom_score_display_settings();
 
             if (!empty($customdisplays) && $scoredisplay->is_custom()) {
@@ -533,7 +533,7 @@ if (isset($_POST['action'])) {
             case 'delete':
                 $number_of_deleted_results = 0;
                 foreach ($_POST['id'] as $indexstr) {
-                    $result = Result :: load($indexstr);
+                    $result = Result::load($indexstr);
                     $result[0]->delete();
                     $number_of_deleted_results++;
                 }
diff --git a/main/gradebook/index.php b/main/gradebook/index.php
index f611a0cd21..9d8b3cacb4 100755
--- a/main/gradebook/index.php
+++ b/main/gradebook/index.php
@@ -740,7 +740,7 @@ if (isset($_GET['studentoverview'])) {
     // then Category::load() will create a new 'root' category with empty
     // course and session fields in memory (Category::create_root_category())
 
-    $cats = Category:: load(
+    $cats = Category::load(
         null,
         null,
         $course_code,
diff --git a/main/gradebook/lib/fe/catform.class.php b/main/gradebook/lib/fe/catform.class.php
index cd639b434d..278d179f8b 100755
--- a/main/gradebook/lib/fe/catform.class.php
+++ b/main/gradebook/lib/fe/catform.class.php
@@ -8,10 +8,10 @@
  */
 class CatForm extends FormValidator
 {
-    const TYPE_ADD = 1;
-    const TYPE_EDIT = 2;
-    const TYPE_MOVE = 3;
-    const TYPE_SELECT_COURSE = 4;
+    public const TYPE_ADD = 1;
+    public const TYPE_EDIT = 2;
+    public const TYPE_MOVE = 3;
+    public const TYPE_SELECT_COURSE = 4;
     /** @var Category */
     private $category_object;
 
diff --git a/main/gradebook/lib/fe/dataform.class.php b/main/gradebook/lib/fe/dataform.class.php
index 1a11d063da..9cc14259dd 100755
--- a/main/gradebook/lib/fe/dataform.class.php
+++ b/main/gradebook/lib/fe/dataform.class.php
@@ -8,9 +8,9 @@
  */
 class DataForm extends FormValidator
 {
-    const TYPE_IMPORT = 1;
-    const TYPE_EXPORT = 2;
-    const TYPE_EXPORT_PDF = 3;
+    public const TYPE_IMPORT = 1;
+    public const TYPE_EXPORT = 2;
+    public const TYPE_EXPORT_PDF = 3;
 
     /**
      * Builds a form containing form items based on a given parameter.
@@ -30,7 +30,7 @@ class DataForm extends FormValidator
         $target = '',
         $locked_status
     ) {
-        parent:: __construct($form_name, $method, $action, $target);
+        parent::__construct($form_name, $method, $action, $target);
         $this->form_type = $form_type;
         if ($this->form_type == self::TYPE_IMPORT) {
             $this->build_import_form();
diff --git a/main/gradebook/lib/fe/evalform.class.php b/main/gradebook/lib/fe/evalform.class.php
index 7ffe955110..25887f4240 100755
--- a/main/gradebook/lib/fe/evalform.class.php
+++ b/main/gradebook/lib/fe/evalform.class.php
@@ -10,13 +10,13 @@
  */
 class EvalForm extends FormValidator
 {
-    const TYPE_ADD = 1;
-    const TYPE_EDIT = 2;
-    const TYPE_MOVE = 3;
-    const TYPE_RESULT_ADD = 4;
-    const TYPE_RESULT_EDIT = 5;
-    const TYPE_ALL_RESULTS_EDIT = 6;
-    const TYPE_ADD_USERS_TO_EVAL = 7;
+    public const TYPE_ADD = 1;
+    public const TYPE_EDIT = 2;
+    public const TYPE_MOVE = 3;
+    public const TYPE_RESULT_ADD = 4;
+    public const TYPE_RESULT_EDIT = 5;
+    public const TYPE_ALL_RESULTS_EDIT = 6;
+    public const TYPE_ADD_USERS_TO_EVAL = 7;
 
     protected $evaluation_object;
     private $result_object;
@@ -564,7 +564,7 @@ class EvalForm extends FormValidator
 
         $session_id = api_get_session_id();
         $course_code = api_get_course_id();
-        $all_categories = Category:: load(
+        $all_categories = Category::load(
             null,
             null,
             $course_code,
diff --git a/main/gradebook/lib/fe/flatviewtable.class.php b/main/gradebook/lib/fe/flatviewtable.class.php
index 9bf4e3a520..01a18c9983 100755
--- a/main/gradebook/lib/fe/flatviewtable.class.php
+++ b/main/gradebook/lib/fe/flatviewtable.class.php
@@ -43,7 +43,7 @@ class FlatViewTable extends SortableTable
         $addparams = null,
         $mainCourseCategory = null
     ) {
-        parent:: __construct(
+        parent::__construct(
             'flatviewlist',
             null,
             null,
diff --git a/main/gradebook/lib/fe/linkaddeditform.class.php b/main/gradebook/lib/fe/linkaddeditform.class.php
index 5f19bdefa5..8db7cb1d2d 100755
--- a/main/gradebook/lib/fe/linkaddeditform.class.php
+++ b/main/gradebook/lib/fe/linkaddeditform.class.php
@@ -10,8 +10,8 @@
  */
 class LinkAddEditForm extends FormValidator
 {
-    const TYPE_ADD = 1;
-    const TYPE_EDIT = 2;
+    public const TYPE_ADD = 1;
+    public const TYPE_EDIT = 2;
 
     /**
      * Constructor
@@ -32,7 +32,7 @@ class LinkAddEditForm extends FormValidator
         if (isset($link_object)) {
             $link = $link_object;
         } elseif (isset($link_type) && isset($category_object)) {
-            $link = LinkFactory:: create($link_type);
+            $link = LinkFactory::create($link_type);
             $link->set_course_code(api_get_course_id());
             $link->set_session_id(api_get_session_id());
             $link->set_category_id($category_object[0]->get_id());
diff --git a/main/gradebook/lib/fe/linkform.class.php b/main/gradebook/lib/fe/linkform.class.php
index 1e64daab35..ac8424803f 100755
--- a/main/gradebook/lib/fe/linkform.class.php
+++ b/main/gradebook/lib/fe/linkform.class.php
@@ -11,8 +11,8 @@
  */
 class LinkForm extends FormValidator
 {
-    const TYPE_CREATE = 1;
-    const TYPE_MOVE = 2;
+    public const TYPE_CREATE = 1;
+    public const TYPE_MOVE = 2;
     /** @var Category */
     private $category_object;
     private $link_object;
diff --git a/main/gradebook/lib/fe/resulttable.class.php b/main/gradebook/lib/fe/resulttable.class.php
index fc35f398a6..eb9f37bef9 100755
--- a/main/gradebook/lib/fe/resulttable.class.php
+++ b/main/gradebook/lib/fe/resulttable.class.php
@@ -31,7 +31,7 @@ class ResultTable extends SortableTable
         $addparams = [],
         $forprint = false
     ) {
-        parent:: __construct(
+        parent::__construct(
             'resultlist',
             null,
             null,
diff --git a/main/gradebook/lib/fe/userform.class.php b/main/gradebook/lib/fe/userform.class.php
index 85e18ecb35..57ddada43a 100755
--- a/main/gradebook/lib/fe/userform.class.php
+++ b/main/gradebook/lib/fe/userform.class.php
@@ -9,8 +9,8 @@
  */
 class UserForm extends FormValidator
 {
-    const TYPE_USER_INFO = 1;
-    const TYPE_SIMPLE_SEARCH = 3;
+    public const TYPE_USER_INFO = 1;
+    public const TYPE_SIMPLE_SEARCH = 3;
 
     /**
      * Builds a form containing form items based on a given parameter.
diff --git a/main/gradebook/lib/flatview_data_generator.class.php b/main/gradebook/lib/flatview_data_generator.class.php
index 563db5bfcd..d768bbf3a9 100755
--- a/main/gradebook/lib/flatview_data_generator.class.php
+++ b/main/gradebook/lib/flatview_data_generator.class.php
@@ -11,10 +11,10 @@
 class FlatViewDataGenerator
 {
     // Sorting types constants
-    const FVDG_SORT_LASTNAME = 1;
-    const FVDG_SORT_FIRSTNAME = 2;
-    const FVDG_SORT_ASC = 4;
-    const FVDG_SORT_DESC = 8;
+    public const FVDG_SORT_LASTNAME = 1;
+    public const FVDG_SORT_FIRSTNAME = 2;
+    public const FVDG_SORT_ASC = 4;
+    public const FVDG_SORT_DESC = 8;
     public $params;
     /** @var Category */
     public $category;
diff --git a/main/gradebook/lib/gradebook_data_generator.class.php b/main/gradebook/lib/gradebook_data_generator.class.php
index 10b6c9a871..3828c77e92 100755
--- a/main/gradebook/lib/gradebook_data_generator.class.php
+++ b/main/gradebook/lib/gradebook_data_generator.class.php
@@ -14,14 +14,14 @@ use ChamiloSession as Session;
 class GradebookDataGenerator
 {
     // Sorting types constants
-    const GDG_SORT_TYPE = 1;
-    const GDG_SORT_NAME = 2;
-    const GDG_SORT_DESCRIPTION = 4;
-    const GDG_SORT_WEIGHT = 8;
-    const GDG_SORT_DATE = 16;
-    const GDG_SORT_ASC = 32;
-    const GDG_SORT_DESC = 64;
-    const GDG_SORT_ID = 128;
+    public const GDG_SORT_TYPE = 1;
+    public const GDG_SORT_NAME = 2;
+    public const GDG_SORT_DESCRIPTION = 4;
+    public const GDG_SORT_WEIGHT = 8;
+    public const GDG_SORT_DATE = 16;
+    public const GDG_SORT_ASC = 32;
+    public const GDG_SORT_DESC = 64;
+    public const GDG_SORT_ID = 128;
     public $userId;
     public $hidePercentage = false;
 
diff --git a/main/gradebook/lib/results_data_generator.class.php b/main/gradebook/lib/results_data_generator.class.php
index 5fde377829..15031d58f3 100755
--- a/main/gradebook/lib/results_data_generator.class.php
+++ b/main/gradebook/lib/results_data_generator.class.php
@@ -11,13 +11,13 @@
 class ResultsDataGenerator
 {
     // Sorting types constants
-    const RDG_SORT_LASTNAME = 1;
-    const RDG_SORT_FIRSTNAME = 2;
-    const RDG_SORT_SCORE = 4;
-    const RDG_SORT_MASK = 8;
+    public const RDG_SORT_LASTNAME = 1;
+    public const RDG_SORT_FIRSTNAME = 2;
+    public const RDG_SORT_SCORE = 4;
+    public const RDG_SORT_MASK = 8;
 
-    const RDG_SORT_ASC = 16;
-    const RDG_SORT_DESC = 32;
+    public const RDG_SORT_ASC = 16;
+    public const RDG_SORT_DESC = 32;
     private $evaluation;
     private $results;
     private $is_course_ind;
diff --git a/main/gradebook/lib/user_data_generator.class.php b/main/gradebook/lib/user_data_generator.class.php
index 55e8241ff7..2fda43a5fb 100755
--- a/main/gradebook/lib/user_data_generator.class.php
+++ b/main/gradebook/lib/user_data_generator.class.php
@@ -11,16 +11,16 @@
 class UserDataGenerator
 {
     // Sorting types constants
-    const UDG_SORT_TYPE = 1;
-    const UDG_SORT_NAME = 2;
-    const UDG_SORT_COURSE = 4;
-    const UDG_SORT_CATEGORY = 8;
-    const UDG_SORT_AVERAGE = 16;
-    const UDG_SORT_SCORE = 32;
-    const UDG_SORT_MASK = 64;
-
-    const UDG_SORT_ASC = 128;
-    const UDG_SORT_DESC = 256;
+    public const UDG_SORT_TYPE = 1;
+    public const UDG_SORT_NAME = 2;
+    public const UDG_SORT_COURSE = 4;
+    public const UDG_SORT_CATEGORY = 8;
+    public const UDG_SORT_AVERAGE = 16;
+    public const UDG_SORT_SCORE = 32;
+    public const UDG_SORT_MASK = 64;
+
+    public const UDG_SORT_ASC = 128;
+    public const UDG_SORT_DESC = 256;
 
     private $items;
     private $userid;
diff --git a/main/gradebook/user_stats.php b/main/gradebook/user_stats.php
index 82f7ecbc97..b49d15f226 100755
--- a/main/gradebook/user_stats.php
+++ b/main/gradebook/user_stats.php
@@ -49,7 +49,7 @@ if (isset($_GET['exportpdf'])) {
         true
     );
     $newarray = [];
-    $displayscore = ScoreDisplay :: instance();
+    $displayscore = ScoreDisplay::instance();
     foreach ($data_array as $data) {
         $newarray[] = array_slice($data, 1);
     }
diff --git a/main/group/group_creation.php b/main/group/group_creation.php
index d4b74aee46..14d5d07a66 100755
--- a/main/group/group_creation.php
+++ b/main/group/group_creation.php
@@ -326,7 +326,7 @@ EOT;
         $classForm->addHtml($description);
         $classForm->addElement('hidden', 'action');
         if (api_get_setting('allow_group_categories') === 'true') {
-            $group_categories = GroupManager :: get_categories();
+            $group_categories = GroupManager::get_categories();
             $cat_options = [];
             foreach ($group_categories as $index => $category) {
                 $cat_options[$category['id']] = $category['title'];
diff --git a/main/group/group_space.php b/main/group/group_space.php
index d9ddec97bb..1434e2afa4 100755
--- a/main/group/group_space.php
+++ b/main/group/group_space.php
@@ -89,7 +89,7 @@ if (GroupManager::is_self_registration_allowed($user_id, $current_group)) {
  * Unregister from group
  */
 $unsubscribe_group = '';
-if (GroupManager :: is_self_unregistration_allowed($user_id, $current_group)) {
+if (GroupManager::is_self_unregistration_allowed($user_id, $current_group)) {
     $unsubscribe_group = '<a class="btn btn-default" href="'.api_get_self().'?selfUnReg=1" onclick="javascript: if(!confirm('."'".addslashes(api_htmlentities(get_lang('ConfirmYourChoice'), ENT_QUOTES))."'".')) return false;">'.
         get_lang('StudentUnsubscribe').'</a>';
 }
diff --git a/main/group/member_settings.php b/main/group/member_settings.php
index 47a976cf9c..8ef63da0d3 100755
--- a/main/group/member_settings.php
+++ b/main/group/member_settings.php
@@ -211,7 +211,7 @@ $action = isset($_GET['action']) ? $_GET['action'] : null;
 switch ($action) {
     case 'empty':
         if (api_is_allowed_to_edit(false, true)) {
-            GroupManager:: unsubscribe_all_users($current_group);
+            GroupManager::unsubscribe_all_users($current_group);
             echo Display::return_message(get_lang('GroupEmptied'), 'confirm');
         }
         break;
diff --git a/main/group/settings.php b/main/group/settings.php
index 9ccd0e56db..62b7b53166 100755
--- a/main/group/settings.php
+++ b/main/group/settings.php
@@ -389,4 +389,4 @@ echo '<div class="row">';
 $form->display();
 echo '</div>';
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/group/tutor_settings.php b/main/group/tutor_settings.php
index c248613379..4825ce3eef 100755
--- a/main/group/tutor_settings.php
+++ b/main/group/tutor_settings.php
@@ -164,7 +164,7 @@ if ($form->validate()) {
     $values = $form->exportValues();
 
     // Storing the tutors (we first remove all the tutors and then add only those who were selected)
-    GroupManager :: unsubscribe_all_tutors($current_group['iid']);
+    GroupManager::unsubscribe_all_tutors($current_group['iid']);
     if (isset($_POST['group_tutors']) && count($_POST['group_tutors']) > 0) {
         GroupManager::subscribe_tutors($values['group_tutors'], $current_group);
     }
@@ -195,9 +195,9 @@ if (!empty($_GET['keyword']) && !empty($_GET['submit'])) {
     echo '<br/>'.get_lang('SearchResultsFor').' <span style="font-style: italic ;"> '.$keyword_name.' </span><br>';
 }
 
-Display :: display_header($nameTools, 'Group');
+Display::display_header($nameTools, 'Group');
 $form->setDefaults($defaults);
 echo GroupManager::getSettingBar('tutor');
 $form->display();
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/help/allowed_html_tags.php b/main/help/allowed_html_tags.php
index 140aa340f3..13466f24d0 100755
--- a/main/help/allowed_html_tags.php
+++ b/main/help/allowed_html_tags.php
@@ -45,7 +45,7 @@ if (api_get_setting('stylesheets') != '') {
 $html_type = $_SESSION['status'] == COURSEMANAGER ? TEACHER_HTML : STUDENT_HTML;
 
 $fullpage = intval($_GET['fullpage']) != 0;
-$tags = HTML_QuickForm_Rule_HTML :: get_allowed_tags($html_type, $fullpage);
+$tags = HTML_QuickForm_Rule_HTML::get_allowed_tags($html_type, $fullpage);
 $table_header = [];
 $table_header[] = ['tag', true];
 $table_header[] = ['attributes', false];
diff --git a/main/inc/ajax/gradebook.ajax.php b/main/inc/ajax/gradebook.ajax.php
index 056c09dcbd..18e0e08a39 100755
--- a/main/inc/ajax/gradebook.ajax.php
+++ b/main/inc/ajax/gradebook.ajax.php
@@ -29,7 +29,7 @@ switch ($action) {
     case 'get_gradebook_weight':
         if (api_is_allowed_to_edit(null, true)) {
             $cat_id = $_GET['cat_id'];
-            $cat = Category :: load($cat_id);
+            $cat = Category::load($cat_id);
             if ($cat && isset($cat[0])) {
                 echo $cat[0]->get_weight();
             } else {
diff --git a/main/inc/ajax/lang.ajax.php b/main/inc/ajax/lang.ajax.php
index 813d1b6de0..2b07c01fd8 100644
--- a/main/inc/ajax/lang.ajax.php
+++ b/main/inc/ajax/lang.ajax.php
@@ -28,7 +28,7 @@ switch ($action) {
             $languageId = (int) $_REQUEST['id'];
             $subLanguageId = (int) $_REQUEST['sub'];
 
-            $langFilesToLoad = SubLanguageManager:: get_lang_folder_files_list(
+            $langFilesToLoad = SubLanguageManager::get_lang_folder_files_list(
                 api_get_path(SYS_LANG_PATH).'english',
                 true
             );
diff --git a/main/inc/global.inc.php b/main/inc/global.inc.php
index 5c7b4c57bd..e303b387bf 100755
--- a/main/inc/global.inc.php
+++ b/main/inc/global.inc.php
@@ -378,7 +378,7 @@ $langpath = api_get_path(SYS_LANG_PATH);
 /* This will only work if we are in the page to edit a sub_language */
 if (isset($this_script) && $this_script == 'sub_language') {
     // getting the arrays of files i.e notification, trad4all, etc
-    $language_files_to_load = SubLanguageManager:: get_lang_folder_files_list(
+    $language_files_to_load = SubLanguageManager::get_lang_folder_files_list(
         api_get_path(SYS_LANG_PATH).'english',
         true
     );
diff --git a/main/inc/lib/Compilatio.php b/main/inc/lib/Compilatio.php
index 4c1175891e..56058a6adb 100644
--- a/main/inc/lib/Compilatio.php
+++ b/main/inc/lib/Compilatio.php
@@ -478,7 +478,7 @@ class Compilatio
             return false;
         }
 
-        $table = Database:: get_course_table(TABLE_PLAGIARISM);
+        $table = Database::get_course_table(TABLE_PLAGIARISM);
         $params = [$courseId, $itemId];
         Database::delete($table, ['c_id = ? AND document_id = ?' => $params]);
 
diff --git a/main/inc/lib/CourseChatUtils.php b/main/inc/lib/CourseChatUtils.php
index cb0ae551c3..fa3f200635 100644
--- a/main/inc/lib/CourseChatUtils.php
+++ b/main/inc/lib/CourseChatUtils.php
@@ -463,7 +463,7 @@ class CourseChatUtils
         $document_path = api_get_path(SYS_COURSE_PATH).$courseInfo['path'].'/document';
         $group_info = [];
         if ($this->groupId) {
-            $group_info = GroupManager:: get_group_properties($this->groupId);
+            $group_info = GroupManager::get_group_properties($this->groupId);
             $basepath_chat = $group_info['directory'].'/chat_files';
         }
 
diff --git a/main/inc/lib/NotificationEvent.php b/main/inc/lib/NotificationEvent.php
index 30452c841d..c2c1863928 100644
--- a/main/inc/lib/NotificationEvent.php
+++ b/main/inc/lib/NotificationEvent.php
@@ -3,10 +3,10 @@
 
 class NotificationEvent extends Model
 {
-    const ACCOUNT_EXPIRATION = 1;
-    const JUSTIFICATION_EXPIRATION = 2;
-    const GLOBAL_NOTIFICATION = 3;
-    const SPECIFIC_USER = 4;
+    public const ACCOUNT_EXPIRATION = 1;
+    public const JUSTIFICATION_EXPIRATION = 2;
+    public const GLOBAL_NOTIFICATION = 3;
+    public const SPECIFIC_USER = 4;
 
     public $table;
     public $columns = [
diff --git a/main/inc/lib/SmsPlugin.php b/main/inc/lib/SmsPlugin.php
index a11f903ae8..f429cb46c1 100644
--- a/main/inc/lib/SmsPlugin.php
+++ b/main/inc/lib/SmsPlugin.php
@@ -8,50 +8,50 @@
  */
 class SmsPlugin extends Plugin
 {
-    const WELCOME_LOGIN_PASSWORD = 0;
-    const NEW_FILE_SHARED_COURSE_BY = 1;
-    const ACCOUNT_APPROVED_CONNECT = 2;
-    const NEW_COURSE_BEEN_CREATED = 3;
-    const NEW_USER_SUBSCRIBED_COURSE = 4;
-    const NEW_COURSE_SUGGESTED_TEACHER = 5;
-    const COURSE_OPENING_REQUEST_CODE_REGISTERED = 6;
-    const COURSE_OPENING_REQUEST_CODE_APPROVED = 7;
-    const COURSE_OPENING_REQUEST_CODE_REJECTED = 8;
-    const COURSE_OPENING_REQUEST_CODE = 9;
-    const BEEN_SUBSCRIBED_COURSE = 10;
-    const ASSIGNMENT_BEEN_CREATED_COURSE = 11;
-    const ACCOUNT_CREATED_UPDATED_LOGIN_PASSWORD = 12;
-    const PASSWORD_UPDATED_LOGIN_PASSWORD = 13;
-    const REQUESTED_PASSWORD_CHANGE = 14;
-    const RECEIVED_NEW_PERSONAL_MESSAGES = 15;
-    const NEW_USER_PENDING_APPROVAL = 16;
-    const POSTED_FORUM_COURSE = 17;
-    const CHECK_EMAIL_CONNECT_MORE_INFO = 18;
-    const STUDENT_ANSWERED_TEST = 19;
-    const STUDENT_ANSWERED_TEST_OPEN_QUESTION = 20;
-    const STUDENT_ANSWERED_TEST_VOICE_QUESTION = 21;
-    const ANSWER_OPEN_QUESTION_TEST_REVIEWED = 22;
-    const NEW_THREAD_STARTED_FORUM = 23;
-    const NEW_ANSWER_POSTED_FORUM = 24;
-    const NEW_SYSTEM_ANNOUNCEMENT_ADDED = 25;
-    const TEST_NEW_SYSTEM_ANNOUNCEMENT_ADDED = 26;
-    const SYSTEM_ANNOUNCEMENT_UPDATE = 27;
-    const TEST_SYSTEM_ANNOUNCEMENT_UPDATE = 28;
-    const USER_UPLOADED_ASSIGNMENT_COURSE_STUDENT_SUBMITS_PAPER = 29;
-    const USER_UPLOADED_ASSIGNMENT_CHECK_STUDENT_SUBMITS_PAPER = 30;
-    const USER_UPLOADED_ASSIGNMENT_COURSE = 31;
-    const USER_UPLOADED_ASSIGNMENT_CHECK = 32;
-    const SUBSCRIBED_SESSION = 33;
-    const SUBSCRIBED_SESSION_CSV = 34;
-    const USER_SUGGESTED_BE_FRIENDS = 35;
-    const USER_ANSWERED_INBOX_MESSAGE = 36;
-    const BEEN_INVITED_JOIN_GROUP = 37;
-    const MESSAGES_SENT_EDITED_GROUP_EDITED = 38;
-    const MESSAGES_SENT_EDITED_GROUP_ADDED = 39;
-    const BEEN_INVITED_COMPLETE_SURVEY_COURSE = 40;
-    const REMINDER_ASSIGNMENT_COURSE_DUE = 41;
-    const USER_DETAILS_MODIFIED = 42;
-    const CERTIFICATE_NOTIFICATION = 43;
+    public const WELCOME_LOGIN_PASSWORD = 0;
+    public const NEW_FILE_SHARED_COURSE_BY = 1;
+    public const ACCOUNT_APPROVED_CONNECT = 2;
+    public const NEW_COURSE_BEEN_CREATED = 3;
+    public const NEW_USER_SUBSCRIBED_COURSE = 4;
+    public const NEW_COURSE_SUGGESTED_TEACHER = 5;
+    public const COURSE_OPENING_REQUEST_CODE_REGISTERED = 6;
+    public const COURSE_OPENING_REQUEST_CODE_APPROVED = 7;
+    public const COURSE_OPENING_REQUEST_CODE_REJECTED = 8;
+    public const COURSE_OPENING_REQUEST_CODE = 9;
+    public const BEEN_SUBSCRIBED_COURSE = 10;
+    public const ASSIGNMENT_BEEN_CREATED_COURSE = 11;
+    public const ACCOUNT_CREATED_UPDATED_LOGIN_PASSWORD = 12;
+    public const PASSWORD_UPDATED_LOGIN_PASSWORD = 13;
+    public const REQUESTED_PASSWORD_CHANGE = 14;
+    public const RECEIVED_NEW_PERSONAL_MESSAGES = 15;
+    public const NEW_USER_PENDING_APPROVAL = 16;
+    public const POSTED_FORUM_COURSE = 17;
+    public const CHECK_EMAIL_CONNECT_MORE_INFO = 18;
+    public const STUDENT_ANSWERED_TEST = 19;
+    public const STUDENT_ANSWERED_TEST_OPEN_QUESTION = 20;
+    public const STUDENT_ANSWERED_TEST_VOICE_QUESTION = 21;
+    public const ANSWER_OPEN_QUESTION_TEST_REVIEWED = 22;
+    public const NEW_THREAD_STARTED_FORUM = 23;
+    public const NEW_ANSWER_POSTED_FORUM = 24;
+    public const NEW_SYSTEM_ANNOUNCEMENT_ADDED = 25;
+    public const TEST_NEW_SYSTEM_ANNOUNCEMENT_ADDED = 26;
+    public const SYSTEM_ANNOUNCEMENT_UPDATE = 27;
+    public const TEST_SYSTEM_ANNOUNCEMENT_UPDATE = 28;
+    public const USER_UPLOADED_ASSIGNMENT_COURSE_STUDENT_SUBMITS_PAPER = 29;
+    public const USER_UPLOADED_ASSIGNMENT_CHECK_STUDENT_SUBMITS_PAPER = 30;
+    public const USER_UPLOADED_ASSIGNMENT_COURSE = 31;
+    public const USER_UPLOADED_ASSIGNMENT_CHECK = 32;
+    public const SUBSCRIBED_SESSION = 33;
+    public const SUBSCRIBED_SESSION_CSV = 34;
+    public const USER_SUGGESTED_BE_FRIENDS = 35;
+    public const USER_ANSWERED_INBOX_MESSAGE = 36;
+    public const BEEN_INVITED_JOIN_GROUP = 37;
+    public const MESSAGES_SENT_EDITED_GROUP_EDITED = 38;
+    public const MESSAGES_SENT_EDITED_GROUP_ADDED = 39;
+    public const BEEN_INVITED_COMPLETE_SURVEY_COURSE = 40;
+    public const REMINDER_ASSIGNMENT_COURSE_DUE = 41;
+    public const USER_DETAILS_MODIFIED = 42;
+    public const CERTIFICATE_NOTIFICATION = 43;
 
     public $isCoursePlugin = true;
     public $isMailPlugin = true;
diff --git a/main/inc/lib/SortableTableFromArray.php b/main/inc/lib/SortableTableFromArray.php
index 03fc1e7245..6437e0c92a 100644
--- a/main/inc/lib/SortableTableFromArray.php
+++ b/main/inc/lib/SortableTableFromArray.php
@@ -31,7 +31,7 @@ class SortableTableFromArray extends SortableTable
         $get_total_number_function = null,
         $tableId = ''
     ) {
-        parent:: __construct(
+        parent::__construct(
             $tableName,
             $get_total_number_function,
             null,
diff --git a/main/inc/lib/StudentFollowPage.php b/main/inc/lib/StudentFollowPage.php
index e2c6ead66e..f6583b1e62 100644
--- a/main/inc/lib/StudentFollowPage.php
+++ b/main/inc/lib/StudentFollowPage.php
@@ -9,8 +9,8 @@ use Chamilo\CourseBundle\Entity\CItemProperty;
  */
 class StudentFollowPage
 {
-    const VARIABLE_ACQUISITION = 'acquisition';
-    const VARIABLE_INVISIBLE = 'invisible';
+    public const VARIABLE_ACQUISITION = 'acquisition';
+    public const VARIABLE_INVISIBLE = 'invisible';
 
     public static function getLpSubscription(
         array $lpInfo,
diff --git a/main/inc/lib/TicketManager.php b/main/inc/lib/TicketManager.php
index cf5ae93fc2..b997f3e440 100644
--- a/main/inc/lib/TicketManager.php
+++ b/main/inc/lib/TicketManager.php
@@ -14,20 +14,20 @@ use Chamilo\TicketBundle\Entity\Ticket;
  */
 class TicketManager
 {
-    const PRIORITY_NORMAL = 'NRM';
-    const PRIORITY_HIGH = 'HGH';
-    const PRIORITY_LOW = 'LOW';
-
-    const SOURCE_EMAIL = 'MAI';
-    const SOURCE_PHONE = 'TEL';
-    const SOURCE_PLATFORM = 'PLA';
-    const SOURCE_PRESENTIAL = 'PRE';
-
-    const STATUS_NEW = 'NAT';
-    const STATUS_PENDING = 'PND';
-    const STATUS_UNCONFIRMED = 'XCF';
-    const STATUS_CLOSE = 'CLS';
-    const STATUS_FORWARDED = 'REE';
+    public const PRIORITY_NORMAL = 'NRM';
+    public const PRIORITY_HIGH = 'HGH';
+    public const PRIORITY_LOW = 'LOW';
+
+    public const SOURCE_EMAIL = 'MAI';
+    public const SOURCE_PHONE = 'TEL';
+    public const SOURCE_PLATFORM = 'PLA';
+    public const SOURCE_PRESENTIAL = 'PRE';
+
+    public const STATUS_NEW = 'NAT';
+    public const STATUS_PENDING = 'PND';
+    public const STATUS_UNCONFIRMED = 'XCF';
+    public const STATUS_CLOSE = 'CLS';
+    public const STATUS_FORWARDED = 'REE';
 
     /**
      * Constructor.
diff --git a/main/inc/lib/add_course.lib.inc.php b/main/inc/lib/add_course.lib.inc.php
index 5e47600eac..5410b0b700 100755
--- a/main/inc/lib/add_course.lib.inc.php
+++ b/main/inc/lib/add_course.lib.inc.php
@@ -848,7 +848,7 @@ class AddCourse
                                         "INSERT INTO $TABLETOOLDOCUMENT (c_id, path,title,filetype,size)
                                         VALUES ($course_id,'$path_documents".$folder_path."','".$title."','folder','0')"
                                     );
-                                    $image_id = Database:: insert_id();
+                                    $image_id = Database::insert_id();
 
                                     Database::insert(
                                         $TABLEITEMPROPERTY,
@@ -899,7 +899,7 @@ class AddCourse
                                         "INSERT INTO $TABLETOOLDOCUMENT (c_id, path,title,filetype,size)
                                         VALUES ($course_id,'$path_documents".$value["file"]."','".$temp[count($temp) - 1]."','file','$file_size')"
                                     );
-                                    $image_id = Database:: insert_id();
+                                    $image_id = Database::insert_id();
                                     if ($image_id) {
                                         $sql = "UPDATE $TABLETOOLDOCUMENT SET id = iid WHERE iid = $image_id";
                                         Database::query($sql);
@@ -1098,12 +1098,12 @@ class AddCourse
                 "INSERT INTO $TABLEGRADEBOOK (name, description, user_id, course_code, parent_id, weight, visible, certif_min_score, session_id, document_id)
                 VALUES ('$course_code','',1,'$course_code',0,100,0,75,NULL,$example_cert_id)"
             );
-            $gbid = Database:: insert_id();
+            $gbid = Database::insert_id();
             Database::query(
                 "INSERT INTO $TABLEGRADEBOOK (name, description, user_id, course_code, parent_id, weight, visible, certif_min_score, session_id, document_id)
                 VALUES ('$course_code','',1,'$course_code',$gbid,100,1,75,NULL,$example_cert_id)"
             );
-            $gbid = Database:: insert_id();
+            $gbid = Database::insert_id();
             Database::query(
                 "INSERT INTO $TABLEGRADEBOOKLINK (type, ref_id, user_id, course_code, category_id, created_at, weight, visible, locked)
                 VALUES (1,$exercise_id,1,'$course_code',$gbid,'$now',100,1,0)"
@@ -1132,7 +1132,7 @@ class AddCourse
         $sql = "INSERT INTO $tableDocument (id, c_id, path,title,filetype,size, readonly, session_id)
                 VALUES ($counter, $course_id, '".$file['path']."', '".$file['title']."', '".$file['filetype']."', '".$file['size']."', 0, 0)";
         Database::query($sql);
-        $docId = Database:: insert_id();
+        $docId = Database::insert_id();
 
         $authorId = empty($authorId) ? api_get_user_id() : (int) $authorId;
 
@@ -1330,7 +1330,7 @@ class AddCourse
                 // Default true
                 $addTeacher = isset($params['add_user_as_teacher']) ? $params['add_user_as_teacher'] : true;
                 if ($addTeacher) {
-                    $i_course_sort = CourseManager:: userCourseSort(
+                    $i_course_sort = CourseManager::userCourseSort(
                         $user_id,
                         $code
                     );
diff --git a/main/inc/lib/agenda.lib.php b/main/inc/lib/agenda.lib.php
index 562447d37e..9331b69d49 100644
--- a/main/inc/lib/agenda.lib.php
+++ b/main/inc/lib/agenda.lib.php
@@ -4432,7 +4432,7 @@ class Agenda
                 $course['db']
             );
             // get the groups to which the user belong
-            $group_memberships = GroupManager:: get_group_ids(
+            $group_memberships = GroupManager::get_group_ids(
                 $course['db'],
                 $user_id
             );
diff --git a/main/inc/lib/attendance.lib.php b/main/inc/lib/attendance.lib.php
index 6a4a6cab6f..b203f0a525 100755
--- a/main/inc/lib/attendance.lib.php
+++ b/main/inc/lib/attendance.lib.php
@@ -13,9 +13,9 @@
 class Attendance
 {
     // constants
-    const DONE_ATTENDANCE_LOG_TYPE = 'done_attendance_sheet';
-    const UPDATED_ATTENDANCE_LOG_TYPE = 'updated_attendance_sheet';
-    const LOCKED_ATTENDANCE_LOG_TYPE = 'locked_attendance_sheet';
+    public const DONE_ATTENDANCE_LOG_TYPE = 'done_attendance_sheet';
+    public const UPDATED_ATTENDANCE_LOG_TYPE = 'updated_attendance_sheet';
+    public const LOCKED_ATTENDANCE_LOG_TYPE = 'locked_attendance_sheet';
     public $category_id;
     private $session_id;
     private $course_id;
@@ -689,14 +689,14 @@ class Attendance
         $studentInGroup = [];
 
         if (!empty($current_session_id)) {
-            $a_course_users = CourseManager:: get_user_list_from_course_code(
+            $a_course_users = CourseManager::get_user_list_from_course_code(
                 $current_course_id,
                 $current_session_id,
                 '',
                 'lastname'
             );
         } else {
-            $a_course_users = CourseManager:: get_user_list_from_course_code(
+            $a_course_users = CourseManager::get_user_list_from_course_code(
                 $current_course_id,
                 0,
                 '',
diff --git a/main/inc/lib/blog.lib.php b/main/inc/lib/blog.lib.php
index e9f41e5123..a09032026f 100755
--- a/main/inc/lib/blog.lib.php
+++ b/main/inc/lib/blog.lib.php
@@ -2520,7 +2520,7 @@ class Blog
         $column_header[] = [get_lang('Email'), false, ''];
         $column_header[] = [get_lang('Register'), false, ''];
 
-        $student_list = CourseManager:: get_student_list_from_course_code(
+        $student_list = CourseManager::get_student_list_from_course_code(
             $currentCourse,
             false,
             $session_id
diff --git a/main/inc/lib/certificate.lib.php b/main/inc/lib/certificate.lib.php
index 5858b72cca..14130cd07f 100755
--- a/main/inc/lib/certificate.lib.php
+++ b/main/inc/lib/certificate.lib.php
@@ -929,7 +929,7 @@ class Certificate extends Model
                         if (!empty($sessionData['courses'])) {
                             $sessionId = $sessionData['session_id'];
                             foreach ($sessionData['courses'] as $courseData) {
-                                $cats = Category:: load(
+                                $cats = Category::load(
                                     null,
                                     null,
                                     $courseData['course_code'],
diff --git a/main/inc/lib/chamilo_session.class.php b/main/inc/lib/chamilo_session.class.php
index f112166967..e4b52574a9 100755
--- a/main/inc/lib/chamilo_session.class.php
+++ b/main/inc/lib/chamilo_session.class.php
@@ -28,7 +28,7 @@ use Symfony\Component\HttpFoundation\Session\Session;
  */
 class ChamiloSession extends System\Session
 {
-    const NAME = 'ch_sid';
+    public const NAME = 'ch_sid';
 
     /**
      * Generate new session instance.
diff --git a/main/inc/lib/course.lib.php b/main/inc/lib/course.lib.php
index e1a771cb2e..f3099fee9b 100755
--- a/main/inc/lib/course.lib.php
+++ b/main/inc/lib/course.lib.php
@@ -26,11 +26,11 @@ use Doctrine\Common\Collections\Criteria;
  */
 class CourseManager
 {
-    const MAX_COURSE_LENGTH_CODE = 40;
+    public const MAX_COURSE_LENGTH_CODE = 40;
     /** This constant is used to show separate user names in the course
      * list (userportal), footer, etc */
-    const USER_SEPARATOR = ' |';
-    const COURSE_FIELD_TYPE_CHECKBOX = 10;
+    public const USER_SEPARATOR = ' |';
+    public const COURSE_FIELD_TYPE_CHECKBOX = 10;
     public $columns = [];
 
     /**
@@ -1732,7 +1732,7 @@ class CourseManager
                         $users[$row_key]['count_users_registered'] = $registered_users_with_extra_field;
                         $users[$row_key]['average_hours_per_user'] = $users[$row_key]['training_hours'] / $users[$row_key]['count_users'];
 
-                        $category = Category:: load(
+                        $category = Category::load(
                             null,
                             null,
                             $course_code,
@@ -1773,7 +1773,7 @@ class CourseManager
                             )
                         );
 
-                        $category = Category:: load(
+                        $category = Category::load(
                             null,
                             null,
                             $course_code,
diff --git a/main/inc/lib/custom_pages.class.php b/main/inc/lib/custom_pages.class.php
index 8e77688f85..f606afada2 100755
--- a/main/inc/lib/custom_pages.class.php
+++ b/main/inc/lib/custom_pages.class.php
@@ -10,12 +10,12 @@
  */
 class CustomPages
 {
-    const INDEX_LOGGED = 'index-logged';
-    const INDEX_UNLOGGED = 'index-unlogged';
-    const LOGGED_OUT = 'loggedout';
-    const REGISTRATION_FEEDBACK = 'registration-feedback';
-    const REGISTRATION = 'registration';
-    const LOST_PASSWORD = 'lostpassword';
+    public const INDEX_LOGGED = 'index-logged';
+    public const INDEX_UNLOGGED = 'index-unlogged';
+    public const LOGGED_OUT = 'loggedout';
+    public const REGISTRATION_FEEDBACK = 'registration-feedback';
+    public const REGISTRATION = 'registration';
+    public const LOST_PASSWORD = 'lostpassword';
 
     /**
      * Returns true if custom pages are enabled. False otherwise.
diff --git a/main/inc/lib/diagnoser.lib.php b/main/inc/lib/diagnoser.lib.php
index 6ce537542a..e3aceefcfd 100755
--- a/main/inc/lib/diagnoser.lib.php
+++ b/main/inc/lib/diagnoser.lib.php
@@ -13,10 +13,10 @@
  */
 class Diagnoser
 {
-    const STATUS_OK = 1;
-    const STATUS_WARNING = 2;
-    const STATUS_ERROR = 3;
-    const STATUS_INFORMATION = 4;
+    public const STATUS_OK = 1;
+    public const STATUS_WARNING = 2;
+    public const STATUS_ERROR = 3;
+    public const STATUS_INFORMATION = 4;
 
     /**
      * Contructor.
diff --git a/main/inc/lib/exercise.lib.php b/main/inc/lib/exercise.lib.php
index 24383e9ebc..e24e01cf89 100644
--- a/main/inc/lib/exercise.lib.php
+++ b/main/inc/lib/exercise.lib.php
@@ -2853,7 +2853,7 @@ HOTSPOT;
                             switch ($revised) {
                                 case 0:
                                     $actions .= "<a href='exercise_show.php?".$cidReq."&action=qualify&id=$id'>".
-                                        Display:: return_icon(
+                                        Display::return_icon(
                                             'quiz.png',
                                             get_lang('Qualify')
                                         );
@@ -2865,7 +2865,7 @@ HOTSPOT;
                                     break;
                                 case 1:
                                     $actions .= "<a href='exercise_show.php?".$cidReq."&action=edit&id=$id'>".
-                                        Display:: return_icon(
+                                        Display::return_icon(
                                             'edit.png',
                                             get_lang('Edit'),
                                             [],
@@ -2883,7 +2883,7 @@ HOTSPOT;
                                         .'&exerciseId='.$exercise_id
                                         .'&a=close&id='.$id
                                         .'">'.
-                                        Display:: return_icon(
+                                        Display::return_icon(
                                             'lock.png',
                                             get_lang('MarkAttemptAsClosed'),
                                             [],
@@ -2896,7 +2896,7 @@ HOTSPOT;
                                     );
                                     break;
                                 case 3: //still ongoing
-                                    $actions .= Display:: return_icon(
+                                    $actions .= Display::return_icon(
                                         'clock.png',
                                         get_lang('AttemptStillOngoingPleaseWait'),
                                         [],
@@ -2912,7 +2912,7 @@ HOTSPOT;
 
                             if ($filter == 2) {
                                 $actions .= ' <a href="exercise_history.php?'.$cidReq.'&exe_id='.$id.'">'.
-                                    Display:: return_icon(
+                                    Display::return_icon(
                                         'history.png',
                                         get_lang('ViewHistoryChange')
                                     ).'</a>';
diff --git a/main/inc/lib/fileManage.lib.php b/main/inc/lib/fileManage.lib.php
index 9f00976c59..b83dc858c2 100755
--- a/main/inc/lib/fileManage.lib.php
+++ b/main/inc/lib/fileManage.lib.php
@@ -43,7 +43,7 @@ function check_name_exist($file_path)
  *
  * @author - Hugues Peeters
  *
- * @param  $file (String) - the path of file or directory to delete
+ * @param $file (String) - the path of file or directory to delete
  *
  * @return bool - true if the delete succeed, false otherwise
  *
diff --git a/main/inc/lib/formvalidator/FormValidator.class.php b/main/inc/lib/formvalidator/FormValidator.class.php
index 8d894941b3..56d39f8675 100755
--- a/main/inc/lib/formvalidator/FormValidator.class.php
+++ b/main/inc/lib/formvalidator/FormValidator.class.php
@@ -8,11 +8,11 @@
  */
 class FormValidator extends HTML_QuickForm
 {
-    const LAYOUT_HORIZONTAL = 'horizontal';
-    const LAYOUT_INLINE = 'inline';
-    const LAYOUT_BOX = 'box';
-    const LAYOUT_BOX_NO_LABEL = 'box-no-label';
-    const LAYOUT_GRID = 'grid';
+    public const LAYOUT_HORIZONTAL = 'horizontal';
+    public const LAYOUT_INLINE = 'inline';
+    public const LAYOUT_BOX = 'box';
+    public const LAYOUT_BOX_NO_LABEL = 'box-no-label';
+    public const LAYOUT_GRID = 'grid';
 
     public $with_progress_bar = false;
     private $layout;
diff --git a/main/inc/lib/groupmanager.lib.php b/main/inc/lib/groupmanager.lib.php
index b20c20d310..82ec89d6e6 100755
--- a/main/inc/lib/groupmanager.lib.php
+++ b/main/inc/lib/groupmanager.lib.php
@@ -17,45 +17,45 @@ class GroupManager
     /* DEFAULT_GROUP_CATEGORY:
     When group categories aren't available (platform-setting),
     all groups are created in this 'dummy'-category*/
-    const DEFAULT_GROUP_CATEGORY = 2;
+    public const DEFAULT_GROUP_CATEGORY = 2;
 
     /**
      * infinite.
      */
-    const INFINITE = 99999;
+    public const INFINITE = 99999;
     /**
      * No limit on the number of users in a group.
      */
-    const MEMBER_PER_GROUP_NO_LIMIT = 0;
+    public const MEMBER_PER_GROUP_NO_LIMIT = 0;
     /**
      * No limit on the number of groups per user.
      */
-    const GROUP_PER_MEMBER_NO_LIMIT = 0;
+    public const GROUP_PER_MEMBER_NO_LIMIT = 0;
     /**
      * The tools of a group can have 3 states
      * - not available
      * - public
      * - private.
      */
-    const TOOL_NOT_AVAILABLE = 0;
-    const TOOL_PUBLIC = 1;
-    const TOOL_PRIVATE = 2;
-    const TOOL_PRIVATE_BETWEEN_USERS = 3;
+    public const TOOL_NOT_AVAILABLE = 0;
+    public const TOOL_PUBLIC = 1;
+    public const TOOL_PRIVATE = 2;
+    public const TOOL_PRIVATE_BETWEEN_USERS = 3;
 
     /**
      * Constants for the available group tools.
      */
-    const GROUP_TOOL_FORUM = 0;
-    const GROUP_TOOL_DOCUMENTS = 1;
-    const GROUP_TOOL_CALENDAR = 2;
-    const GROUP_TOOL_ANNOUNCEMENT = 3;
-    const GROUP_TOOL_WORK = 4;
-    const GROUP_TOOL_WIKI = 5;
-    const GROUP_TOOL_CHAT = 6;
-
-    const DOCUMENT_MODE_SHARE = 0; // By default
-    const DOCUMENT_MODE_READ_ONLY = 1;
-    const DOCUMENT_MODE_COLLABORATION = 2;
+    public const GROUP_TOOL_FORUM = 0;
+    public const GROUP_TOOL_DOCUMENTS = 1;
+    public const GROUP_TOOL_CALENDAR = 2;
+    public const GROUP_TOOL_ANNOUNCEMENT = 3;
+    public const GROUP_TOOL_WORK = 4;
+    public const GROUP_TOOL_WIKI = 5;
+    public const GROUP_TOOL_CHAT = 6;
+
+    public const DOCUMENT_MODE_SHARE = 0; // By default
+    public const DOCUMENT_MODE_READ_ONLY = 1;
+    public const DOCUMENT_MODE_COLLABORATION = 2;
 
     /**
      * GroupManager constructor.
diff --git a/main/inc/lib/link.lib.php b/main/inc/lib/link.lib.php
index 0d3ea8798d..1b93f7a0f6 100755
--- a/main/inc/lib/link.lib.php
+++ b/main/inc/lib/link.lib.php
@@ -85,8 +85,8 @@ class Link extends Model
                 WHERE
                     c_id = $courseId AND
                     category_id = '".intval($params['category_id'])."'";
-        $result = Database:: query($sql);
-        list($orderMax) = Database:: fetch_row($result);
+        $result = Database::query($sql);
+        list($orderMax) = Database::fetch_row($result);
         $order = $orderMax + 1;
         $params['display_order'] = $order;
 
@@ -282,9 +282,9 @@ class Link extends Model
                             (int) $selectcategory,
                             $course_int_id
                         );
-                        $result = Database:: query($sql_cat);
-                        if (Database:: num_rows($result) == 1) {
-                            $row = Database:: fetch_array($result);
+                        $result = Database::query($sql_cat);
+                        if (Database::num_rows($result) == 1) {
+                            $row = Database::fetch_array($result);
                             $ic_slide->addValue(
                                 'category',
                                 $row['category_title']
@@ -293,7 +293,7 @@ class Link extends Model
                     }
 
                     $di = new ChamiloIndexer();
-                    isset($_POST['language']) ? $lang = Database:: escape_string(
+                    isset($_POST['language']) ? $lang = Database::escape_string(
                         $_POST['language']
                     ) : $lang = 'english';
                     $di->connectDb(null, null, $lang);
@@ -317,7 +317,7 @@ class Link extends Model
                             $link_id,
                             $did
                         );
-                        Database:: query($sql);
+                        Database::query($sql);
                     }
                 }
                 Display::addFlash(Display::return_message(get_lang('LinkAdded')));
@@ -335,11 +335,11 @@ class Link extends Model
                 $ok = false;
             } else {
                 // Looking for the largest order number for this category.
-                $result = Database:: query(
+                $result = Database::query(
                     "SELECT MAX(display_order) FROM  $tbl_categories
                     WHERE c_id = $course_id "
                 );
-                list($orderMax) = Database:: fetch_row($result);
+                list($orderMax) = Database::fetch_row($result);
                 $order = $orderMax + 1;
                 $order = intval($order);
                 $session_id = api_get_session_id();
@@ -356,7 +356,7 @@ class Link extends Model
                 if ($linkId) {
                     // iid
                     $sql = "UPDATE $tbl_categories SET id = iid WHERE iid = $linkId";
-                    Database:: query($sql);
+                    Database::query($sql);
 
                     // add link_category visibility
                     // course ID is taken from context in api_set_default_visibility
@@ -411,7 +411,7 @@ class Link extends Model
                 // This will make a restore function possible for the platform administrator.
                 $sql = "UPDATE $tbl_link SET on_homepage='0'
                         WHERE c_id = $course_id AND id='".$id."'";
-                Database:: query($sql);
+                Database::query($sql);
 
                 api_item_property_update(
                     $courseInfo,
@@ -429,11 +429,11 @@ class Link extends Model
                 // First we delete the category itself and afterwards all the links of this category.
                 $sql = "DELETE FROM ".$tbl_categories."
                         WHERE c_id = $course_id AND id='".$id."'";
-                Database:: query($sql);
+                Database::query($sql);
 
                 $sql = "DELETE FROM ".$tbl_link."
                         WHERE c_id = $course_id AND category_id='".$id."'";
-                Database:: query($sql);
+                Database::query($sql);
 
                 api_item_property_update(
                     $courseInfo,
@@ -466,15 +466,15 @@ class Link extends Model
             );
             $sql = 'SELECT * FROM %s WHERE course_code=\'%s\' AND tool_id=\'%s\' AND ref_id_high_level=%s LIMIT 1';
             $sql = sprintf($sql, $tbl_se_ref, $course_id, TOOL_LINK, $link_id);
-            $res = Database:: query($sql);
-            if (Database:: num_rows($res) > 0) {
+            $res = Database::query($sql);
+            if (Database::num_rows($res) > 0) {
                 $row = Database::fetch_array($res);
                 $di = new ChamiloIndexer();
                 $di->remove_document($row['search_did']);
             }
             $sql = 'DELETE FROM %s WHERE course_code=\'%s\' AND tool_id=\'%s\' AND ref_id_high_level=%s LIMIT 1';
             $sql = sprintf($sql, $tbl_se_ref, $course_id, TOOL_LINK, $link_id);
-            Database:: query($sql);
+            Database::query($sql);
 
             // Remove terms from db.
             require_once api_get_path(LIBRARY_PATH).'specific_fields_manager.lib.php';
@@ -554,8 +554,8 @@ class Link extends Model
         // Finding the old category_id.
         $sql = "SELECT * FROM $tbl_link
                 WHERE c_id = $course_id AND id='".$id."'";
-        $result = Database:: query($sql);
-        $row = Database:: fetch_array($result);
+        $result = Database::query($sql);
+        $row = Database::fetch_array($result);
         $category_id = $row['category_id'];
 
         if ($category_id != $values['category_id']) {
@@ -564,8 +564,8 @@ class Link extends Model
                     WHERE
                         c_id = $course_id AND
                         category_id='".intval($values['category_id'])."'";
-            $result = Database:: query($sql);
-            list($max_display_order) = Database:: fetch_row($result);
+            $result = Database::query($sql);
+            list($max_display_order) = Database::fetch_row($result);
             $max_display_order++;
         } else {
             $max_display_order = $row['display_order'];
@@ -590,8 +590,8 @@ class Link extends Model
         if (api_get_setting('search_enabled') === 'true') {
             $course_int_id = api_get_course_int_id();
             $course_id = api_get_course_id();
-            $link_title = Database:: escape_string($values['title']);
-            $link_description = Database:: escape_string($values['description']);
+            $link_title = Database::escape_string($values['title']);
+            $link_description = Database::escape_string($values['description']);
 
             // Actually, it consists on delete terms from db,
             // insert new ones, create a new search engine document, and remove the old one.
@@ -607,12 +607,12 @@ class Link extends Model
                 TOOL_LINK,
                 $id
             );
-            $res = Database:: query($sql);
+            $res = Database::query($sql);
 
-            if (Database:: num_rows($res) > 0) {
+            if (Database::num_rows($res) > 0) {
                 require_once api_get_path(LIBRARY_PATH).'specific_fields_manager.lib.php';
 
-                $se_ref = Database:: fetch_array($res);
+                $se_ref = Database::fetch_array($res);
                 $specific_fields = get_specific_field_list();
                 $ic_slide = new IndexableChunk();
 
@@ -676,9 +676,9 @@ class Link extends Model
                         $categoryId,
                         $course_int_id
                     );
-                    $result = Database:: query($sql_cat);
-                    if (Database:: num_rows($result) == 1) {
-                        $row = Database:: fetch_array($result);
+                    $result = Database::query($sql_cat);
+                    if (Database::num_rows($result) == 1) {
+                        $row = Database::fetch_array($result);
                         $ic_slide->addValue(
                             'category',
                             $row['category_title']
@@ -687,7 +687,7 @@ class Link extends Model
                 }
 
                 $di = new ChamiloIndexer();
-                isset($_POST['language']) ? $lang = Database:: escape_string($_POST['language']) : $lang = 'english';
+                isset($_POST['language']) ? $lang = Database::escape_string($_POST['language']) : $lang = 'english';
                 $di->connectDb(null, null, $lang);
                 $di->remove_document($se_ref['search_did']);
                 $di->addChunk($ic_slide);
@@ -707,7 +707,7 @@ class Link extends Model
                         TOOL_LINK,
                         $id
                     );
-                    Database:: query($sql);
+                    Database::query($sql);
                     $sql = 'INSERT INTO %s (c_id, id, course_code, tool_id, ref_id_high_level, search_did)
                             VALUES (NULL , \'%s\', \'%s\', %s, %s)';
                     $sql = sprintf(
@@ -719,7 +719,7 @@ class Link extends Model
                         $id,
                         $did
                     );
-                    Database:: query($sql);
+                    Database::query($sql);
                 }
             }
         }
@@ -955,7 +955,7 @@ class Link extends Model
                     $condition
                 ORDER BY link.display_order ASC, ip.session_id DESC";
 
-        $result = Database:: query($sql);
+        $result = Database::query($sql);
 
         return Database::store_result($result);
     }
@@ -1179,7 +1179,7 @@ class Link extends Model
         $categoryId = $category['id'];
         $token = null;
         $tools = '<a href="'.api_get_self().'?'.api_get_cidreq().'&sec_token='.$token.'&action=editcategory&id='.$categoryId.'&category_id='.$categoryId.'" title='.get_lang('Modify').'">'.
-            Display:: return_icon(
+            Display::return_icon(
                 'edit.png',
                 get_lang('Modify'),
                 [],
@@ -1189,14 +1189,14 @@ class Link extends Model
         // DISPLAY MOVE UP COMMAND only if it is not the top link.
         if ($currentCategory != 0) {
             $tools .= '<a href="'.api_get_self().'?'.api_get_cidreq().'&sec_token='.$token.'&action=up&up='.$categoryId.'&category_id='.$categoryId.'" title="'.get_lang('Up').'">'.
-                Display:: return_icon(
+                Display::return_icon(
                     'up.png',
                     get_lang('Up'),
                     [],
                     ICON_SIZE_SMALL
                 ).'</a>';
         } else {
-            $tools .= Display:: return_icon(
+            $tools .= Display::return_icon(
                 'up_na.png',
                 get_lang('Up'),
                 [],
@@ -1207,14 +1207,14 @@ class Link extends Model
         // DISPLAY MOVE DOWN COMMAND only if it is not the bottom link.
         if ($currentCategory < $countCategories - 1) {
             $tools .= '<a href="'.api_get_self().'?'.api_get_cidreq().'&sec_token='.$token.'&action=down&down='.$categoryId.'&category_id='.$categoryId.'">'.
-                Display:: return_icon(
+                Display::return_icon(
                     'down.png',
                     get_lang('Down'),
                     [],
                     ICON_SIZE_SMALL
                 ).'</a>';
         } else {
-            $tools .= Display:: return_icon(
+            $tools .= Display::return_icon(
                 'down_na.png',
                 get_lang('Down'),
                 [],
@@ -1224,7 +1224,7 @@ class Link extends Model
 
         $tools .= '<a href="'.api_get_self().'?'.api_get_cidreq().'&sec_token='.$token.'&action=deletecategory&id='.$categoryId."&category_id=$categoryId\"
             onclick=\"javascript: if(!confirm('".get_lang('CategoryDelconfirm')."')) return false;\">".
-            Display:: return_icon(
+            Display::return_icon(
                 'delete.png',
                 get_lang('Delete'),
                 [],
@@ -1277,9 +1277,9 @@ class Link extends Model
             $sql = "SELECT id, display_order FROM $movetable
                     WHERE c_id = $courseId
                     ORDER BY display_order $sortDirection";
-            $linkresult = Database:: query($sql);
+            $linkresult = Database::query($sql);
             $thislinkOrder = 1;
-            while ($sortrow = Database:: fetch_array($linkresult)) {
+            while ($sortrow = Database::fetch_array($linkresult)) {
                 // STEP 2 : FOUND THE NEXT LINK ID AND ORDER, COMMIT SWAP
                 // This part seems unlogic, but it isn't . We first look for the current link with the querystring ID
                 // and we know the next iteration of the while loop is the next one. These should be swapped.
@@ -1287,12 +1287,12 @@ class Link extends Model
                     $nextlinkId = $sortrow['id'];
                     $nextlinkOrder = $sortrow['display_order'];
 
-                    Database:: query(
+                    Database::query(
                         "UPDATE ".$movetable."
                         SET display_order = '$nextlinkOrder'
                         WHERE c_id = $courseId  AND id =  '$thiscatlinkId'"
                     );
-                    Database:: query(
+                    Database::query(
                         "UPDATE ".$movetable."
                         SET display_order = '$thislinkOrder'
                         WHERE c_id = $courseId  AND id =  '$nextlinkId'"
diff --git a/main/inc/lib/login.lib.php b/main/inc/lib/login.lib.php
index 1569be7c63..e6ad9d1b67 100755
--- a/main/inc/lib/login.lib.php
+++ b/main/inc/lib/login.lib.php
@@ -128,7 +128,7 @@ class Login
         if ($result == 1) {
             return get_lang('YourPasswordHasBeenReset');
         } else {
-            $mail = Display:: encrypted_mailto_link(
+            $mail = Display::encrypted_mailto_link(
                 api_get_setting('emailAdministrator'),
                 api_get_person_name(
                     api_get_setting('administratorName'),
@@ -201,7 +201,7 @@ class Login
 
             return get_lang('AnEmailToResetYourPasswordHasBeenSent');
         } else {
-            $admin_email = Display:: encrypted_mailto_link(
+            $admin_email = Display::encrypted_mailto_link(
                 api_get_setting('emailAdministrator'),
                 api_get_person_name(
                     api_get_setting('administratorName'),
diff --git a/main/inc/lib/message.lib.php b/main/inc/lib/message.lib.php
index 46e0182f9d..00d7be99dd 100755
--- a/main/inc/lib/message.lib.php
+++ b/main/inc/lib/message.lib.php
@@ -15,9 +15,9 @@ use ChamiloSession as Session;
  */
 class MessageManager
 {
-    const MESSAGE_TYPE_INBOX = 1;
-    const MESSAGE_TYPE_OUTBOX = 2;
-    const MESSAGE_TYPE_PROMOTED = 3;
+    public const MESSAGE_TYPE_INBOX = 1;
+    public const MESSAGE_TYPE_OUTBOX = 2;
+    public const MESSAGE_TYPE_PROMOTED = 3;
 
     /**
      * Get count new messages for the current user from the database.
diff --git a/main/inc/lib/myspace.lib.php b/main/inc/lib/myspace.lib.php
index 41857a5491..9d72e6a5ae 100644
--- a/main/inc/lib/myspace.lib.php
+++ b/main/inc/lib/myspace.lib.php
@@ -2832,7 +2832,7 @@ class MySpace
                         $session_id
                     );
 
-                    $last_login_date_tmp = Tracking:: get_last_connection_date_on_the_course(
+                    $last_login_date_tmp = Tracking::get_last_connection_date_on_the_course(
                         $row_user->user_id,
                         $courseInfo,
                         $session_id,
@@ -3567,7 +3567,7 @@ class MySpace
             // coach only will registered users
             $default_status = STUDENT;
             if ($user['create'] == COURSEMANAGER) {
-                $user['id'] = UserManager:: create_user(
+                $user['id'] = UserManager::create_user(
                     $user['FirstName'],
                     $user['LastName'],
                     $default_status,
diff --git a/main/inc/lib/notification.lib.php b/main/inc/lib/notification.lib.php
index 8997d320d1..11551b65d1 100644
--- a/main/inc/lib/notification.lib.php
+++ b/main/inc/lib/notification.lib.php
@@ -9,29 +9,29 @@
 class Notification extends Model
 {
     // mail_notify_message ("At once", "Daily", "No")
-    const NOTIFY_MESSAGE_AT_ONCE = 1;
-    const NOTIFY_MESSAGE_DAILY = 8;
-    const NOTIFY_MESSAGE_WEEKLY = 12;
-    const NOTIFY_MESSAGE_NO = 0;
+    public const NOTIFY_MESSAGE_AT_ONCE = 1;
+    public const NOTIFY_MESSAGE_DAILY = 8;
+    public const NOTIFY_MESSAGE_WEEKLY = 12;
+    public const NOTIFY_MESSAGE_NO = 0;
 
     // mail_notify_invitation ("At once", "Daily", "No")
-    const NOTIFY_INVITATION_AT_ONCE = 1;
-    const NOTIFY_INVITATION_DAILY = 8;
-    const NOTIFY_INVITATION_WEEKLY = 12;
-    const NOTIFY_INVITATION_NO = 0;
+    public const NOTIFY_INVITATION_AT_ONCE = 1;
+    public const NOTIFY_INVITATION_DAILY = 8;
+    public const NOTIFY_INVITATION_WEEKLY = 12;
+    public const NOTIFY_INVITATION_NO = 0;
 
     // mail_notify_group_message ("At once", "Daily", "No")
-    const NOTIFY_GROUP_AT_ONCE = 1;
-    const NOTIFY_GROUP_DAILY = 8;
-    const NOTIFY_GROUP_WEEKLY = 12;
-    const NOTIFY_GROUP_NO = 0;
+    public const NOTIFY_GROUP_AT_ONCE = 1;
+    public const NOTIFY_GROUP_DAILY = 8;
+    public const NOTIFY_GROUP_WEEKLY = 12;
+    public const NOTIFY_GROUP_NO = 0;
 
     // Notification types
-    const NOTIFICATION_TYPE_MESSAGE = 1;
-    const NOTIFICATION_TYPE_INVITATION = 2;
-    const NOTIFICATION_TYPE_GROUP = 3;
-    const NOTIFICATION_TYPE_WALL_MESSAGE = 4;
-    const NOTIFICATION_TYPE_DIRECT_MESSAGE = 5;
+    public const NOTIFICATION_TYPE_MESSAGE = 1;
+    public const NOTIFICATION_TYPE_INVITATION = 2;
+    public const NOTIFICATION_TYPE_GROUP = 3;
+    public const NOTIFICATION_TYPE_WALL_MESSAGE = 4;
+    public const NOTIFICATION_TYPE_DIRECT_MESSAGE = 5;
     public $table;
     public $columns = [
         'id',
diff --git a/main/inc/lib/plugin.class.php b/main/inc/lib/plugin.class.php
index a694229e50..4ff3586a2b 100755
--- a/main/inc/lib/plugin.class.php
+++ b/main/inc/lib/plugin.class.php
@@ -19,8 +19,8 @@ use Chamilo\CourseBundle\Entity\CTool;
  */
 class Plugin
 {
-    const TAB_FILTER_NO_STUDENT = '::no-student';
-    const TAB_FILTER_ONLY_STUDENT = '::only-student';
+    public const TAB_FILTER_NO_STUDENT = '::no-student';
+    public const TAB_FILTER_ONLY_STUDENT = '::only-student';
     public $isCoursePlugin = false;
     public $isAdminPlugin = false;
     public $isMailPlugin = false;
diff --git a/main/inc/lib/sessionmanager.lib.php b/main/inc/lib/sessionmanager.lib.php
index 568ef87629..616ebc1083 100755
--- a/main/inc/lib/sessionmanager.lib.php
+++ b/main/inc/lib/sessionmanager.lib.php
@@ -25,10 +25,10 @@ use Monolog\Logger;
  */
 class SessionManager
 {
-    const STATUS_PLANNED = 1;
-    const STATUS_PROGRESS = 2;
-    const STATUS_FINISHED = 3;
-    const STATUS_CANCELLED = 4;
+    public const STATUS_PLANNED = 1;
+    public const STATUS_PROGRESS = 2;
+    public const STATUS_FINISHED = 3;
+    public const STATUS_CANCELLED = 4;
 
     public static $_debug = false;
 
@@ -2586,7 +2586,7 @@ class SessionManager
                 if ($copyEvaluation) {
                     $cats = Category::load(null, null, $courseInfo['code']);
                     if (!empty($cats)) {
-                        $sessionCategory = Category:: load(
+                        $sessionCategory = Category::load(
                             null,
                             null,
                             $courseInfo['code'],
diff --git a/main/inc/lib/social.lib.php b/main/inc/lib/social.lib.php
index 462a5d7fa1..1b30db9885 100755
--- a/main/inc/lib/social.lib.php
+++ b/main/inc/lib/social.lib.php
@@ -16,8 +16,8 @@ use Zend\Feed\Reader\Reader;
  */
 class SocialManager extends UserManager
 {
-    const DEFAULT_WALL_POSTS = 10;
-    const DEFAULT_SCROLL_NEW_POST = 5;
+    public const DEFAULT_WALL_POSTS = 10;
+    public const DEFAULT_SCROLL_NEW_POST = 5;
 
     /**
      * Constructor.
diff --git a/main/inc/lib/sortable_table.class.php b/main/inc/lib/sortable_table.class.php
index 409284dcb5..7b3545e375 100755
--- a/main/inc/lib/sortable_table.class.php
+++ b/main/inc/lib/sortable_table.class.php
@@ -300,22 +300,22 @@ class SortableTable extends HTML_Table
             $params['urlVar'] = $this->param_prefix.'page_nr';
             $params['currentPage'] = $this->page_nr;
             $icon_attributes = ['style' => 'vertical-align: middle;'];
-            $params['prevImg'] = Display:: return_icon(
+            $params['prevImg'] = Display::return_icon(
                 'action_prev.png',
                 get_lang('PreviousPage'),
                 $icon_attributes
             );
-            $params['nextImg'] = Display:: return_icon(
+            $params['nextImg'] = Display::return_icon(
                 'action_next.png',
                 get_lang('NextPage'),
                 $icon_attributes
             );
-            $params['firstPageText'] = Display:: return_icon(
+            $params['firstPageText'] = Display::return_icon(
                 'action_first.png',
                 get_lang('FirstPage'),
                 $icon_attributes
             );
-            $params['lastPageText'] = Display:: return_icon(
+            $params['lastPageText'] = Display::return_icon(
                 'action_last.png',
                 get_lang('LastPage'),
                 $icon_attributes
diff --git a/main/inc/lib/statistics.lib.php b/main/inc/lib/statistics.lib.php
index 635f8b9eb3..414f088513 100644
--- a/main/inc/lib/statistics.lib.php
+++ b/main/inc/lib/statistics.lib.php
@@ -1124,7 +1124,7 @@ class Statistics
             $table_header[] = [get_lang("LastAccess"), true];
 
             ob_start();
-            Display:: display_sortable_table(
+            Display::display_sortable_table(
                 $table_header,
                 $courses,
                 ['column' => $column, 'direction' => $direction],
diff --git a/main/inc/lib/usergroup.lib.php b/main/inc/lib/usergroup.lib.php
index 958ec7c0f5..a419ba8b9e 100755
--- a/main/inc/lib/usergroup.lib.php
+++ b/main/inc/lib/usergroup.lib.php
@@ -10,8 +10,8 @@
  */
 class UserGroup extends Model
 {
-    const SOCIAL_CLASS = 1;
-    const NORMAL_CLASS = 0;
+    public const SOCIAL_CLASS = 1;
+    public const NORMAL_CLASS = 0;
     public $columns = [
         'id',
         'name',
diff --git a/main/inc/lib/userportal.lib.php b/main/inc/lib/userportal.lib.php
index 2c101af7c8..fec29791ef 100755
--- a/main/inc/lib/userportal.lib.php
+++ b/main/inc/lib/userportal.lib.php
@@ -655,7 +655,7 @@ class IndexManager
         }
         if ($category != '') {
             $result .= '<p><a href="'.api_get_self().'">'
-                .Display:: return_icon('back.png', get_lang('BackToHomePage'))
+                .Display::return_icon('back.png', get_lang('BackToHomePage'))
                 .get_lang('BackToHomePage').'</a></p>';
         }
 
diff --git a/main/inc/lib/webservices/Rest.php b/main/inc/lib/webservices/Rest.php
index 7a637f206c..29992fe23d 100644
--- a/main/inc/lib/webservices/Rest.php
+++ b/main/inc/lib/webservices/Rest.php
@@ -16,114 +16,114 @@ use Symfony\Component\HttpFoundation\Request as HttpRequest;
  */
 class Rest extends WebService
 {
-    const SERVICE_NAME = 'MsgREST';
-    const EXTRA_FIELD_GCM_REGISTRATION = 'gcm_registration_id';
-
-    const GET_AUTH = 'authenticate';
-    const SAVE_GCM_ID = 'gcm_id';
-    const LOGOUT = 'logout';
-
-    const GET_USER_MESSAGES = 'user_messages';
-    const GET_USER_MESSAGES_RECEIVED = 'user_messages_received';
-    const DELETE_USER_MESSAGE = 'delete_user_message';
-    const GET_USER_MESSAGES_SENT = 'user_messages_sent';
-    const GET_COUNT_NEW_MESSAGES = 'get_count_new_messages';
-    const SET_MESSAGE_READ = 'set_message_read';
-    const POST_USER_MESSAGE_READ = 'user_message_read';
-    const POST_USER_MESSAGE_UNREAD = 'user_message_unread';
-    const SAVE_USER_MESSAGE = 'save_user_message';
-    const GET_MESSAGE_USERS = 'message_users';
-    const VIEW_MESSAGE = 'view_message';
-
-    const GET_USER_COURSES = 'user_courses';
-    const GET_USER_SESSIONS = 'user_sessions';
-
-    const VIEW_PROFILE = 'view_user_profile';
-    const GET_PROFILE = 'user_profile';
-
-    const VIEW_MY_COURSES = 'view_my_courses';
-    const VIEW_COURSE_HOME = 'view_course_home';
-    const GET_COURSE_INFO = 'course_info';
-    const GET_COURSE_DESCRIPTIONS = 'course_descriptions';
-    const GET_COURSE_DOCUMENTS = 'course_documents';
-    const GET_COURSE_ANNOUNCEMENTS = 'course_announcements';
-    const GET_COURSE_ANNOUNCEMENT = 'course_announcement';
-    const GET_COURSE_AGENDA = 'course_agenda';
-    const GET_COURSE_NOTEBOOKS = 'course_notebooks';
-    const GET_COURSE_FORUM_CATEGORIES = 'course_forumcategories';
-    const GET_COURSE_FORUM = 'course_forum';
-    const GET_COURSE_FORUM_THREAD = 'course_forumthread';
-    const GET_COURSE_LEARNPATHS = 'course_learnpaths';
-    const GET_COURSE_LEARNPATH = 'course_learnpath';
-    const GET_COURSE_LP_PROGRESS = 'course_lp_progress';
-    const GET_COURSE_LINKS = 'course_links';
-    const GET_COURSE_WORKS = 'course_works';
-
-    const SAVE_COURSE_NOTEBOOK = 'save_course_notebook';
-
-    const SAVE_FORUM_POST = 'save_forum_post';
-    const SAVE_FORUM_THREAD = 'save_forum_thread';
-    const SET_THREAD_NOTIFY = 'set_thread_notify';
-    const DOWNLOAD_FORUM_ATTACHMENT = 'download_forum_attachment';
-
-    const GET_WORK_LIST = 'get_work_list';
-    const GET_WORK_STUDENTS_WITHOUT_PUBLICATIONS = 'get_work_students_without_publications';
-    const GET_WORK_USERS = 'get_work_users';
-    const GET_WORK_STUDENT_LIST = 'get_work_student_list';
-    const PUT_WORK_STUDENT_ITEM_VISIBILITY = 'put_course_work_visibility';
-    const DELETE_WORK_STUDENT_ITEM = 'delete_work_student_item';
-    const DELETE_WORK_CORRECTIONS = 'delete_work_corrections';
-    const DOWNLOAD_WORK_FOLDER = 'download_work_folder';
-    const DOWNLOAD_WORK_COMMENT_ATTACHMENT = 'download_work_comment_attachment';
-    const DOWNLOAD_WORK = 'download_work';
-
-    const VIEW_DOCUMENT_IN_FRAME = 'view_document_in_frame';
-
-    const VIEW_QUIZ_TOOL = 'view_quiz_tool';
-
-    const VIEW_SURVEY_TOOL = 'view_survey_tool';
-
-    const CREATE_CAMPUS = 'add_campus';
-    const EDIT_CAMPUS = 'edit_campus';
-    const DELETE_CAMPUS = 'delete_campus';
-
-    const GET_USERS = 'get_users';
-    const USERNAME_EXIST = 'username_exist';
-    const SAVE_USER = 'save_user';
-    const SAVE_USER_GET_APIKEY = 'save_user_get_apikey';
-    const SAVE_USER_JSON = 'save_user_json';
-    const UPDATE_USER_FROM_USERNAME = 'update_user_from_username';
-    const UPDATE_USER_APIKEY = 'update_user_apikey';
-    const DELETE_USER = 'delete_user';
-    const GET_USERS_API_KEYS = 'get_users_api_keys';
-    const GET_USER_API_KEY = 'get_user_api_key';
-
-    const GET_COURSES = 'get_courses';
-    const GET_COURSES_FROM_EXTRA_FIELD = 'get_courses_from_extra_field';
-    const SAVE_COURSE = 'save_course';
-    const DELETE_COURSE = 'delete_course';
-
-    const GET_SESSION_FROM_EXTRA_FIELD = 'get_session_from_extra_field';
-    const SAVE_SESSION = 'save_session';
-    const CREATE_SESSION_FROM_MODEL = 'create_session_from_model';
-    const UPDATE_SESSION = 'update_session';
-
-    const SUBSCRIBE_USER_TO_COURSE = 'subscribe_user_to_course';
-    const SUBSCRIBE_USER_TO_COURSE_PASSWORD = 'subscribe_user_to_course_password';
-    const UNSUBSCRIBE_USER_FROM_COURSE = 'unsubscribe_user_from_course';
-    const GET_USERS_SUBSCRIBED_TO_COURSE = 'get_users_subscribed_to_course';
-
-    const ADD_COURSES_SESSION = 'add_courses_session';
-    const ADD_USERS_SESSION = 'add_users_session';
-    const SUBSCRIBE_USER_TO_SESSION_FROM_USERNAME = 'subscribe_user_to_session_from_username';
-
-    const GET_COURSE_QUIZ_MDL_COMPAT = 'get_course_quiz_mdl_compat';
-
-    const UPDATE_USER_PAUSE_TRAINING = 'update_user_pause_training';
-
-    const CHECK_CONDITIONAL_LOGIN = 'check_conditional_login';
-    const GET_LEGAL_CONDITIONS = 'get_legal_conditions';
-    const UPDATE_CONDITION_ACCEPTED = 'update_condition_accepted';
+    public const SERVICE_NAME = 'MsgREST';
+    public const EXTRA_FIELD_GCM_REGISTRATION = 'gcm_registration_id';
+
+    public const GET_AUTH = 'authenticate';
+    public const SAVE_GCM_ID = 'gcm_id';
+    public const LOGOUT = 'logout';
+
+    public const GET_USER_MESSAGES = 'user_messages';
+    public const GET_USER_MESSAGES_RECEIVED = 'user_messages_received';
+    public const DELETE_USER_MESSAGE = 'delete_user_message';
+    public const GET_USER_MESSAGES_SENT = 'user_messages_sent';
+    public const GET_COUNT_NEW_MESSAGES = 'get_count_new_messages';
+    public const SET_MESSAGE_READ = 'set_message_read';
+    public const POST_USER_MESSAGE_READ = 'user_message_read';
+    public const POST_USER_MESSAGE_UNREAD = 'user_message_unread';
+    public const SAVE_USER_MESSAGE = 'save_user_message';
+    public const GET_MESSAGE_USERS = 'message_users';
+    public const VIEW_MESSAGE = 'view_message';
+
+    public const GET_USER_COURSES = 'user_courses';
+    public const GET_USER_SESSIONS = 'user_sessions';
+
+    public const VIEW_PROFILE = 'view_user_profile';
+    public const GET_PROFILE = 'user_profile';
+
+    public const VIEW_MY_COURSES = 'view_my_courses';
+    public const VIEW_COURSE_HOME = 'view_course_home';
+    public const GET_COURSE_INFO = 'course_info';
+    public const GET_COURSE_DESCRIPTIONS = 'course_descriptions';
+    public const GET_COURSE_DOCUMENTS = 'course_documents';
+    public const GET_COURSE_ANNOUNCEMENTS = 'course_announcements';
+    public const GET_COURSE_ANNOUNCEMENT = 'course_announcement';
+    public const GET_COURSE_AGENDA = 'course_agenda';
+    public const GET_COURSE_NOTEBOOKS = 'course_notebooks';
+    public const GET_COURSE_FORUM_CATEGORIES = 'course_forumcategories';
+    public const GET_COURSE_FORUM = 'course_forum';
+    public const GET_COURSE_FORUM_THREAD = 'course_forumthread';
+    public const GET_COURSE_LEARNPATHS = 'course_learnpaths';
+    public const GET_COURSE_LEARNPATH = 'course_learnpath';
+    public const GET_COURSE_LP_PROGRESS = 'course_lp_progress';
+    public const GET_COURSE_LINKS = 'course_links';
+    public const GET_COURSE_WORKS = 'course_works';
+
+    public const SAVE_COURSE_NOTEBOOK = 'save_course_notebook';
+
+    public const SAVE_FORUM_POST = 'save_forum_post';
+    public const SAVE_FORUM_THREAD = 'save_forum_thread';
+    public const SET_THREAD_NOTIFY = 'set_thread_notify';
+    public const DOWNLOAD_FORUM_ATTACHMENT = 'download_forum_attachment';
+
+    public const GET_WORK_LIST = 'get_work_list';
+    public const GET_WORK_STUDENTS_WITHOUT_PUBLICATIONS = 'get_work_students_without_publications';
+    public const GET_WORK_USERS = 'get_work_users';
+    public const GET_WORK_STUDENT_LIST = 'get_work_student_list';
+    public const PUT_WORK_STUDENT_ITEM_VISIBILITY = 'put_course_work_visibility';
+    public const DELETE_WORK_STUDENT_ITEM = 'delete_work_student_item';
+    public const DELETE_WORK_CORRECTIONS = 'delete_work_corrections';
+    public const DOWNLOAD_WORK_FOLDER = 'download_work_folder';
+    public const DOWNLOAD_WORK_COMMENT_ATTACHMENT = 'download_work_comment_attachment';
+    public const DOWNLOAD_WORK = 'download_work';
+
+    public const VIEW_DOCUMENT_IN_FRAME = 'view_document_in_frame';
+
+    public const VIEW_QUIZ_TOOL = 'view_quiz_tool';
+
+    public const VIEW_SURVEY_TOOL = 'view_survey_tool';
+
+    public const CREATE_CAMPUS = 'add_campus';
+    public const EDIT_CAMPUS = 'edit_campus';
+    public const DELETE_CAMPUS = 'delete_campus';
+
+    public const GET_USERS = 'get_users';
+    public const USERNAME_EXIST = 'username_exist';
+    public const SAVE_USER = 'save_user';
+    public const SAVE_USER_GET_APIKEY = 'save_user_get_apikey';
+    public const SAVE_USER_JSON = 'save_user_json';
+    public const UPDATE_USER_FROM_USERNAME = 'update_user_from_username';
+    public const UPDATE_USER_APIKEY = 'update_user_apikey';
+    public const DELETE_USER = 'delete_user';
+    public const GET_USERS_API_KEYS = 'get_users_api_keys';
+    public const GET_USER_API_KEY = 'get_user_api_key';
+
+    public const GET_COURSES = 'get_courses';
+    public const GET_COURSES_FROM_EXTRA_FIELD = 'get_courses_from_extra_field';
+    public const SAVE_COURSE = 'save_course';
+    public const DELETE_COURSE = 'delete_course';
+
+    public const GET_SESSION_FROM_EXTRA_FIELD = 'get_session_from_extra_field';
+    public const SAVE_SESSION = 'save_session';
+    public const CREATE_SESSION_FROM_MODEL = 'create_session_from_model';
+    public const UPDATE_SESSION = 'update_session';
+
+    public const SUBSCRIBE_USER_TO_COURSE = 'subscribe_user_to_course';
+    public const SUBSCRIBE_USER_TO_COURSE_PASSWORD = 'subscribe_user_to_course_password';
+    public const UNSUBSCRIBE_USER_FROM_COURSE = 'unsubscribe_user_from_course';
+    public const GET_USERS_SUBSCRIBED_TO_COURSE = 'get_users_subscribed_to_course';
+
+    public const ADD_COURSES_SESSION = 'add_courses_session';
+    public const ADD_USERS_SESSION = 'add_users_session';
+    public const SUBSCRIBE_USER_TO_SESSION_FROM_USERNAME = 'subscribe_user_to_session_from_username';
+
+    public const GET_COURSE_QUIZ_MDL_COMPAT = 'get_course_quiz_mdl_compat';
+
+    public const UPDATE_USER_PAUSE_TRAINING = 'update_user_pause_training';
+
+    public const CHECK_CONDITIONAL_LOGIN = 'check_conditional_login';
+    public const GET_LEGAL_CONDITIONS = 'get_legal_conditions';
+    public const UPDATE_CONDITION_ACCEPTED = 'update_condition_accepted';
 
     /**
      * @var Session
diff --git a/main/lp/learnpath.class.php b/main/lp/learnpath.class.php
index c8263f4f00..5870e4d3ea 100755
--- a/main/lp/learnpath.class.php
+++ b/main/lp/learnpath.class.php
@@ -359,7 +359,7 @@ class learnpath
                                 ORDER BY view_count DESC ";
                         $status_list = [];
                         $res = Database::query($sql);
-                        while ($row = Database:: fetch_array($res)) {
+                        while ($row = Database::fetch_array($res)) {
                             $status_list[$row['lp_item_id']] = $row['status'];
                         }
 
@@ -3754,7 +3754,7 @@ class learnpath
                                             lp_view_id ='".$lp_view_id."' AND
                                             status='completed'";
                                 $result = Database::query($sql);
-                                $row_count = Database:: fetch_row($result);
+                                $row_count = Database::fetch_row($result);
                                 $count_item_view = (int) $row_count[0];
                                 $not_multiple_attempt = 0;
                                 if ($prevent_reinit === 1 && $count_item_view > 0) {
@@ -7997,7 +7997,7 @@ class learnpath
             $legend .= get_lang('EditCurrentExecice');
         }
         if (isset($_GET['edit']) && $_GET['edit'] == 'true') {
-            $legend .= Display:: return_message(
+            $legend .= Display::return_message(
                 get_lang('Warning').' ! '.get_lang('WarningEditingDocument')
             );
         }
diff --git a/main/mySpace/admin.php b/main/mySpace/admin.php
index f992f17a4a..9e4a28b2cc 100755
--- a/main/mySpace/admin.php
+++ b/main/mySpace/admin.php
@@ -15,7 +15,7 @@ $nameTools = get_lang('Administrators');
 
 api_block_anonymous_users();
 $interbreadcrumb[] = ["url" => "index.php", "name" => get_lang('MySpace')];
-Display :: display_header($nameTools);
+Display::display_header($nameTools);
 
 api_display_tool_title($nameTools);
 
diff --git a/main/mySpace/course.php b/main/mySpace/course.php
index 0ef2b67655..9dbd0971b7 100755
--- a/main/mySpace/course.php
+++ b/main/mySpace/course.php
@@ -59,7 +59,7 @@ if (api_get_setting('add_users_by_coach') == 'true') {
     }
 }
 
-Display :: display_header(get_lang('Courses'));
+Display::display_header(get_lang('Courses'));
 $user_id = 0;
 $a_courses = [];
 $menu_items = [];
@@ -307,11 +307,11 @@ function get_courses($from, $limit, $column, $direction)
             if (count($userIdList) > 0) {
                 $countStudents = count($userIdList);
                 // tracking data
-                $avgProgressInCourse = Tracking :: get_avg_student_progress($userIdList, $courseCode, [], $sessionId);
-                $avgScoreInCourse = Tracking :: get_avg_student_score($userIdList, $courseCode, [], $sessionId);
-                $avgTimeSpentInCourse = Tracking :: get_time_spent_on_the_course($userIdList, $courseInfo['real_id'], $sessionId);
-                $messagesInCourse = Tracking :: count_student_messages($userIdList, $courseCode, $sessionId);
-                $assignmentsInCourse = Tracking :: count_student_assignments($userIdList, $courseCode, $sessionId);
+                $avgProgressInCourse = Tracking::get_avg_student_progress($userIdList, $courseCode, [], $sessionId);
+                $avgScoreInCourse = Tracking::get_avg_student_score($userIdList, $courseCode, [], $sessionId);
+                $avgTimeSpentInCourse = Tracking::get_time_spent_on_the_course($userIdList, $courseInfo['real_id'], $sessionId);
+                $messagesInCourse = Tracking::count_student_messages($userIdList, $courseCode, $sessionId);
+                $assignmentsInCourse = Tracking::count_student_assignments($userIdList, $courseCode, $sessionId);
                 $avgTimeSpentInCourse = api_time_to_hms($avgTimeSpentInCourse / $countStudents);
                 $avgProgressInCourse = round($avgProgressInCourse / $countStudents, 2);
 
@@ -395,4 +395,4 @@ $form->setDefaults($params);
 $form->display();
 $table->display();
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/mySpace/current_courses.php b/main/mySpace/current_courses.php
index dd9085b010..d80922f4e6 100755
--- a/main/mySpace/current_courses.php
+++ b/main/mySpace/current_courses.php
@@ -40,7 +40,7 @@ if (!empty($my_courses)) {
             }
         }
 
-        $tmp_students = CourseManager :: get_student_list_from_course_code($course_code, false);
+        $tmp_students = CourseManager::get_student_list_from_course_code($course_code, false);
 
         //Cleaning students only REAL students
         $students = [];
@@ -69,8 +69,8 @@ if (!empty($my_courses)) {
             $total_tools += $tool['count_access_tool'];
         }
 
-        if (Database :: num_rows($rs_lp) > 0) {
-            while ($learnpath = Database :: fetch_array($rs_lp)) {
+        if (Database::num_rows($rs_lp) > 0) {
+            while ($learnpath = Database::fetch_array($rs_lp)) {
                 $lp_id = $learnpath['id'];
 
                 $lp_items =
diff --git a/main/mySpace/index.php b/main/mySpace/index.php
index 134af0a7c9..ea70875459 100755
--- a/main/mySpace/index.php
+++ b/main/mySpace/index.php
@@ -404,6 +404,6 @@ $view->display_one_col_template();
 // Send the csv file if asked
 if ($export_csv) {
     ob_end_clean();
-    Export:: arrayToCsv($csv_content, 'reporting_index');
+    Export::arrayToCsv($csv_content, 'reporting_index');
     exit;
 }
diff --git a/main/mySpace/progression.php b/main/mySpace/progression.php
index 8b2c83ff55..cf8ee3a65e 100755
--- a/main/mySpace/progression.php
+++ b/main/mySpace/progression.php
@@ -19,7 +19,7 @@ $this_section = SECTION_TRACKING;
 
 api_block_anonymous_users();
 $interbreadcrumb[] = ["url" => "index.php", "name" => get_lang('MySpace')];
-Display :: display_header($nameTools);
+Display::display_header($nameTools);
 
 // Database Table Definitions
 $tbl_course = Database::get_main_table(TABLE_MAIN_COURSE);
@@ -75,4 +75,4 @@ if (Database::num_rows($result_course) > 0) {
     echo get_lang('NoCourse');
 }
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/mySpace/session_admin_teachers.php b/main/mySpace/session_admin_teachers.php
index dc70d3b832..7bf7e24d14 100644
--- a/main/mySpace/session_admin_teachers.php
+++ b/main/mySpace/session_admin_teachers.php
@@ -113,7 +113,7 @@ function get_users($from, $limit, $column, $direction)
             foreach ($courses as $course_code) {
                 $courseInfo = api_get_course_info($course_code);
                 $courseId = $courseInfo['real_id'];
-                if (CourseManager :: is_user_subscribed_in_course($student_id, $course_code, true)) {
+                if (CourseManager::is_user_subscribed_in_course($student_id, $course_code, true)) {
                     $avg_time_spent += Tracking::get_time_spent_on_the_course(
                         $student_id,
                         $courseId,
@@ -273,7 +273,7 @@ if ($export_csv) {
     }
     $csv_content = array_merge($csv_header, $content);
     ob_end_clean();
-    Export :: arrayToCsv($csv_content, 'reporting_teacher_list');
+    Export::arrayToCsv($csv_content, 'reporting_teacher_list');
     exit;
 } else {
     Display::display_header($nameTools);
diff --git a/main/mySpace/student.php b/main/mySpace/student.php
index 62c1321f6e..6b743eb034 100755
--- a/main/mySpace/student.php
+++ b/main/mySpace/student.php
@@ -160,7 +160,7 @@ function get_users($from, $limit, $column, $direction): array
         }
 
         if (isset($_GET['id_session'])) {
-            $courses = Tracking :: get_course_list_in_session_from_student($student_id, $sessionId);
+            $courses = Tracking::get_course_list_in_session_from_student($student_id, $sessionId);
         }
 
         $avg_time_spent = $avg_student_score = $avg_student_progress = 0;
diff --git a/main/mySpace/teachers.php b/main/mySpace/teachers.php
index d536b0f17c..1c66a9b26a 100755
--- a/main/mySpace/teachers.php
+++ b/main/mySpace/teachers.php
@@ -125,7 +125,7 @@ function get_users($from, $limit, $column, $direction)
             foreach ($courses as $course_code) {
                 $courseInfo = api_get_course_info($course_code);
                 $courseId = $courseInfo['real_id'];
-                if (CourseManager :: is_user_subscribed_in_course($student_id, $course_code, true)) {
+                if (CourseManager::is_user_subscribed_in_course($student_id, $course_code, true)) {
                     $avg_time_spent += Tracking::get_time_spent_on_the_course(
                         $student_id,
                         $courseId,
@@ -286,7 +286,7 @@ if ($export_csv) {
     }
     $csv_content = array_merge($csv_header, $content);
     ob_end_clean();
-    Export :: arrayToCsv($csv_content, 'reporting_teacher_list');
+    Export::arrayToCsv($csv_content, 'reporting_teacher_list');
     exit;
 } else {
     Display::display_header($nameTools);
@@ -305,4 +305,4 @@ if ($export_csv) {
     $table->display();
 }
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/mySpace/user_import.php b/main/mySpace/user_import.php
index 5ee672f7e9..d8440db638 100755
--- a/main/mySpace/user_import.php
+++ b/main/mySpace/user_import.php
@@ -87,7 +87,7 @@ if (isset($_POST['formSent']) && $_POST['formSent'] && $_FILES['import_file']['s
     }
 }
 
-Display :: display_header($tool_name);
+Display::display_header($tool_name);
 
 if (isset($_FILES['import_file']) && $_FILES['import_file']['size'] == 0 && $_POST) {
     echo Display::return_message(get_lang('ThisFieldIsRequired'), 'error');
@@ -162,4 +162,4 @@ $form->display();
 </pre>
 </blockquote>
 <?php
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/session/add_courses_to_session.php b/main/session/add_courses_to_session.php
index 0d90d77ab3..6a080abbf2 100644
--- a/main/session/add_courses_to_session.php
+++ b/main/session/add_courses_to_session.php
@@ -257,8 +257,8 @@ unset($Courses);
                     <select name="firstLetterCourse" onchange = "xajax_search_courses(this.value,'multiple', <?php echo $sessionId; ?>)" class="selectpicker form-control">
                         <option value="%">--</option>
                         <?php
-                        echo Display :: get_alphabet_options();
-                echo Display :: get_numeric_options(0, 9, ''); ?>
+                        echo Display::get_alphabet_options();
+                echo Display::get_numeric_options(0, 9, ''); ?>
                     </select>
                 </div>
             <?php
diff --git a/main/session/add_edit_users_to_session.php b/main/session/add_edit_users_to_session.php
index de33f31b3b..5022a76f33 100644
--- a/main/session/add_edit_users_to_session.php
+++ b/main/session/add_edit_users_to_session.php
@@ -230,7 +230,7 @@ function search_users($needle, $type)
         $rs = Database::query($sql);
         $i = 0;
         if ($type == 'single') {
-            while ($user = Database:: fetch_array($rs)) {
+            while ($user = Database::fetch_array($rs)) {
                 $i++;
                 if ($i <= 10) {
                     $person_name =
@@ -252,7 +252,7 @@ function search_users($needle, $type)
         } else {
             global $nosessionUsersList;
             $return .= '<select id="origin_users" name="nosessionUsersList[]" multiple="multiple" size="15" style="width:360px;">';
-            while ($user = Database:: fetch_array($rs)) {
+            while ($user = Database::fetch_array($rs)) {
                 $person_name =
                     $user['lastname'].' '.$user['firstname'].' ('.$user['username'].') '.$user['official_code'];
                 if ($showOfficialCode) {
@@ -737,7 +737,7 @@ $newLinks .= Display::url(
                     <select id="first_letter_user" name="firstLetterUser" onchange="change_select(this.value);">
                         <option value="%">--</option>
                         <?php
-                        echo Display:: get_alphabet_options(); ?>
+                        echo Display::get_alphabet_options(); ?>
                     </select>
                     <br/>
                     <br/>
diff --git a/main/session/add_users_to_session.php b/main/session/add_users_to_session.php
index c73b571b0d..95d01a1f71 100644
--- a/main/session/add_users_to_session.php
+++ b/main/session/add_users_to_session.php
@@ -222,7 +222,7 @@ function search_users($needle, $type)
         $rs = Database::query($sql);
         $i = 0;
         if ($type == 'single') {
-            while ($user = Database:: fetch_array($rs)) {
+            while ($user = Database::fetch_array($rs)) {
                 $i++;
                 if ($i <= 10) {
                     $person_name =
@@ -246,7 +246,7 @@ function search_users($needle, $type)
             $xajax_response->addAssign('ajax_list_users_single', 'innerHTML', api_utf8_encode($return));
         } else {
             $return .= '<select id="origin_users" name="nosessionUsersList[]" multiple="multiple" size="15" style="width:360px;">';
-            while ($user = Database:: fetch_array($rs)) {
+            while ($user = Database::fetch_array($rs)) {
                 $person_name =
                     $user['lastname'].' '.$user['firstname'].' ('.$user['username'].') '.$user['official_code'];
                 if ($showOfficialCode) {
@@ -696,7 +696,7 @@ $newLinks .= Display::url(
                     <select id="first_letter_user" name="firstLetterUser" onchange="change_select(this.value);">
                         <option value="%">--</option>
                         <?php
-                        echo Display:: get_alphabet_options(); ?>
+                        echo Display::get_alphabet_options(); ?>
                     </select>
                     <br/>
                     <br/>
diff --git a/main/session/add_users_to_session_course.php b/main/session/add_users_to_session_course.php
index fc469af449..1f3f8d9adc 100644
--- a/main/session/add_users_to_session_course.php
+++ b/main/session/add_users_to_session_course.php
@@ -245,7 +245,7 @@ function search_users($needle, $type)
         $rs = Database::query($sql);
         $i = 0;
         if ($type == 'single') {
-            while ($user = Database:: fetch_array($rs)) {
+            while ($user = Database::fetch_array($rs)) {
                 $i++;
                 if ($i <= 10) {
                     $person_name =
@@ -266,7 +266,7 @@ function search_users($needle, $type)
             $xajax_response->addAssign('ajax_list_users_single', 'innerHTML', api_utf8_encode($return));
         } else {
             $return .= '<select id="origin_users" name="nosessionUsersList[]" multiple="multiple" size="15" style="width:360px;">';
-            while ($user = Database:: fetch_array($rs)) {
+            while ($user = Database::fetch_array($rs)) {
                 $person_name =
                     $user['lastname'].' '.$user['firstname'].' ('.$user['username'].') '.$user['official_code'];
                 if ($showOfficialCode) {
@@ -763,7 +763,7 @@ if ($add_type == 'multiple') {
                     <select id="first_letter_user" name="firstLetterUser" onchange="change_select(this.value);">
                         <option value="%">--</option>
                         <?php
-                        echo Display:: get_alphabet_options(); ?>
+                        echo Display::get_alphabet_options(); ?>
                     </select>
                     <br/>
                     <br/>
diff --git a/main/session/session_add.php b/main/session/session_add.php
index 1de0004b2a..6c9ac943fd 100644
--- a/main/session/session_add.php
+++ b/main/session/session_add.php
@@ -69,7 +69,7 @@ function search_coachs($needle)
         }
 
         $rs = Database::query($sql);
-        while ($user = Database :: fetch_array($rs)) {
+        while ($user = Database::fetch_array($rs)) {
             $return .= '<a href="javascript: void(0);" onclick="javascript: fill_coach_field(\''.$user['username'].'\')">'.api_get_person_name($user['firstname'], $user['lastname']).' ('.$user['username'].')</a><br />';
         }
     }
diff --git a/main/session/session_course_list.php b/main/session/session_course_list.php
index f7a7ca00cb..9ec0d017c6 100644
--- a/main/session/session_course_list.php
+++ b/main/session/session_course_list.php
@@ -93,7 +93,7 @@ foreach ($Courses as $key => $enreg) {
     $tableCourses[] = $course;
 }
 echo '<form method="post" action="'.api_get_self().'">';
-Display :: display_sortable_table($tableHeader, $tableCourses, [], []);
+Display::display_sortable_table($tableHeader, $tableCourses, [], []);
 echo '<select name="action">
 	<option value="delete">'.get_lang('UnsubscribeCoursesFromSession').'</option>
 	</select>
diff --git a/main/session/session_user_edit.php b/main/session/session_user_edit.php
index 758ccaa2bd..998b6e9a36 100644
--- a/main/session/session_user_edit.php
+++ b/main/session/session_user_edit.php
@@ -92,4 +92,4 @@ Display::display_header(get_lang('Edit'));
 echo $message;
 $form->display();
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/social/group_waiting_list.php b/main/social/group_waiting_list.php
index 5e1cc3b3fb..e48d5d375c 100755
--- a/main/social/group_waiting_list.php
+++ b/main/social/group_waiting_list.php
@@ -106,7 +106,7 @@ foreach ($users as $user) {
 
 $social_right_content = '';
 if (empty($new_member_list) > 0) {
-    $social_right_content = Display :: return_message(get_lang('ThereAreNotUsersInTheWaitingList'));
+    $social_right_content = Display::return_message(get_lang('ThereAreNotUsersInTheWaitingList'));
 }
 
 $tpl = new Template(null);
diff --git a/main/social/search.php b/main/social/search.php
index 7bd01704e8..55cca18dd6 100755
--- a/main/social/search.php
+++ b/main/social/search.php
@@ -228,7 +228,7 @@ if ($query != '' || ($query_vars['search_type'] == '1' && count($query_vars) > 2
             [],
             $totalGroups
         );
-        $block_search .= Display:: panelCollapse(
+        $block_search .= Display::panelCollapse(
             get_lang('Groups'),
             $block_groups,
             'search-groups',
diff --git a/main/survey/fillsurvey.php b/main/survey/fillsurvey.php
index 862d58c224..43867ce4c6 100755
--- a/main/survey/fillsurvey.php
+++ b/main/survey/fillsurvey.php
@@ -132,7 +132,7 @@ if ('auto' === $invitationcode && isset($_GET['scode'])) {
     $sql = "SELECT * FROM $table_survey
             WHERE c_id = $course_id AND code = '".Database::escape_string($surveyCode)."'";
     $result = Database::query($sql);
-    if (Database :: num_rows($result) > 0) {
+    if (Database::num_rows($result) > 0) {
         // Check availability
         $row = Database::fetch_array($result, 'ASSOC');
         $tempdata = SurveyManager::get_survey($row['survey_id']);
@@ -147,7 +147,7 @@ if ('auto' === $invitationcode && isset($_GET['scode'])) {
                     $lpItemCondition";
         $result = Database::query($sql);
         $now = api_get_utc_datetime();
-        if (0 == Database :: num_rows($result)) {
+        if (0 == Database::num_rows($result)) {
             $params = [
                 'c_id' => $course_id,
                 'survey_code' => $surveyCode,
@@ -649,7 +649,7 @@ if ($survey_data['form_fields'] &&
 
                 foreach ($user_data as $key => $value) {
                     if (in_array($key, $allowedFields)) {
-                        $sql .= " $key = '".Database :: escape_string($value)."',";
+                        $sql .= " $key = '".Database::escape_string($value)."',";
                         $update = true;
                     }
                 }
@@ -852,7 +852,7 @@ if ((isset($_GET['show']) && $_GET['show'] != '') ||
             $counter = 0;
             $limit = 0;
             $questions = [];
-            while ($row = Database :: fetch_array($result, 'ASSOC')) {
+            while ($row = Database::fetch_array($result, 'ASSOC')) {
                 // If the type is not a pagebreak we store it in the $questions array
                 if ($row['type'] !== 'pagebreak') {
                     $sort = $row['sort'];
@@ -922,7 +922,7 @@ if ((isset($_GET['show']) && $_GET['show'] != '') ||
                     ";
 
             $result = Database::query($sql);
-            while ($row = Database :: fetch_array($result)) {
+            while ($row = Database::fetch_array($result)) {
                 $answer_list['value'] = $row['value'];
                 $answer_list['group'] = $row['survey_group_pri'];
                 $results[] = $answer_list;
@@ -1263,7 +1263,7 @@ if ((isset($_GET['show']) && $_GET['show'] != '') ||
                                 survey_question.question_id IN (".$imploded.")
                             ORDER $order_sql ";
                     $result = Database::query($sql);
-                    $question_counter_max = Database :: num_rows($result);
+                    $question_counter_max = Database::num_rows($result);
                 }
             }
 
@@ -1271,7 +1271,7 @@ if ((isset($_GET['show']) && $_GET['show'] != '') ||
                 $counter = 0;
                 $limit = 0;
                 $questions = [];
-                while ($row = Database :: fetch_array($result, 'ASSOC')) {
+                while ($row = Database::fetch_array($result, 'ASSOC')) {
                     // If the type is not a pagebreak we store it in the $questions array
                     if ('pagebreak' !== $row['type']) {
                         $questions[$row['sort']]['question_id'] = $row['question_id'];
diff --git a/main/survey/survey.lib.php b/main/survey/survey.lib.php
index 895bdd160a..344a61e41e 100755
--- a/main/survey/survey.lib.php
+++ b/main/survey/survey.lib.php
@@ -2139,9 +2139,9 @@ class SurveyManager
     public static function emptySurveyFromId($surveyId)
     {
         // Database table definitions
-        $surveyInvitationTable = Database:: get_course_table(TABLE_SURVEY_INVITATION);
-        $surveyAnswerTable = Database:: get_course_table(TABLE_SURVEY_ANSWER);
-        $surveyTable = Database:: get_course_table(TABLE_SURVEY);
+        $surveyInvitationTable = Database::get_course_table(TABLE_SURVEY_INVITATION);
+        $surveyAnswerTable = Database::get_course_table(TABLE_SURVEY_ANSWER);
+        $surveyTable = Database::get_course_table(TABLE_SURVEY);
         $surveyId = (int) $surveyId;
         $surveyData = self::get_survey($surveyId);
         if (empty($surveyData)) {
@@ -2479,7 +2479,7 @@ class SurveyManager
             case 'by_user':
                 if (null === $groupId) {
                     $sessionId = api_get_session_id();
-                    $users = CourseManager:: get_student_list_from_course_code(
+                    $users = CourseManager::get_student_list_from_course_code(
                         api_get_course_id(),
                         !empty($sessionId),
                         $sessionId
@@ -2843,7 +2843,7 @@ class SurveyManager
         if ($currentDate < $startDate) {
             api_not_allowed(
                 true,
-                Display:: return_message(
+                Display::return_message(
                     get_lang('SurveyNotAvailableYet'),
                     'warning',
                     false
@@ -2854,7 +2854,7 @@ class SurveyManager
         if ($currentDate > $endDate) {
             api_not_allowed(
                 true,
-                Display:: return_message(
+                Display::return_message(
                     get_lang('SurveyNotAvailableAnymore'),
                     'warning',
                     false
diff --git a/main/tracking/course_log_tools.php b/main/tracking/course_log_tools.php
index 726c5f541c..cc05283661 100755
--- a/main/tracking/course_log_tools.php
+++ b/main/tracking/course_log_tools.php
@@ -78,7 +78,7 @@ Display::display_header($nameTools, 'Tracking');
 // getting all the students of the course
 if (empty($session_id)) {
     // Registered students in a course outside session.
-    $students = CourseManager:: get_student_list_from_course_code(
+    $students = CourseManager::get_student_list_from_course_code(
         api_get_course_id(),
         false,
         0,
@@ -89,7 +89,7 @@ if (empty($session_id)) {
     );
 } else {
     // Registered students in session.
-    $students = CourseManager:: get_student_list_from_course_code(
+    $students = CourseManager::get_student_list_from_course_code(
         api_get_course_id(),
         true,
         api_get_session_id()
@@ -464,7 +464,7 @@ if ($linkReporting) {
 // send the csv file if asked
 if ($export_csv) {
     ob_end_clean();
-    Export:: arrayToCsv($csv_content, 'reporting_course_tools');
+    Export::arrayToCsv($csv_content, 'reporting_course_tools');
     exit;
 }
 
diff --git a/main/tracking/course_session_report.php b/main/tracking/course_session_report.php
index 6ff0c2b2ba..2289210470 100755
--- a/main/tracking/course_session_report.php
+++ b/main/tracking/course_session_report.php
@@ -59,7 +59,7 @@ $form->setDefaults(['session_id' => $session_id]);
 $course_list = SessionManager::get_course_list_by_session_id($session_id);
 
 if (!$export_to_xls) {
-    Display :: display_header(get_lang("MySpace"));
+    Display::display_header(get_lang("MySpace"));
     echo '<div class="actions">';
 
     if ($global) {
diff --git a/main/tracking/exams.php b/main/tracking/exams.php
index b3d6cb9d9d..ac4d65725f 100755
--- a/main/tracking/exams.php
+++ b/main/tracking/exams.php
@@ -85,7 +85,7 @@ $exerciseId = isset($_REQUEST['exercise_id']) ? intval($_REQUEST['exercise_id'])
 $form->setDefaults(['score' => $filter_score]);
 
 if (!$exportToXLS) {
-    Display :: display_header(get_lang('Reporting'));
+    Display::display_header(get_lang('Reporting'));
     $actionsLeft = $actionsRight = '';
     if ($global) {
         $actionsLeft .= '<a href="'.api_get_path(WEB_CODE_PATH).'auth/my_progress.php">'.
@@ -727,4 +727,4 @@ function processStudentList($filter_score, $global, $exercise, $courseInfo, $ses
         'total_students' => $totalStudents,
     ];
 }
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/tracking/lp_results_by_user.php b/main/tracking/lp_results_by_user.php
index 6668cad164..7deefd6a1a 100755
--- a/main/tracking/lp_results_by_user.php
+++ b/main/tracking/lp_results_by_user.php
@@ -27,7 +27,7 @@ if (api_is_platform_admin()) {
 }
 
 if ($global) {
-    $temp_course_list = CourseManager :: get_courses_list();
+    $temp_course_list = CourseManager::get_courses_list();
     foreach ($temp_course_list as $temp_course_item) {
         $course_item = api_get_course_info($temp_course_item['code']);
         $course_list[] = [
@@ -81,7 +81,7 @@ if (!empty($selected_course)) {
 }
 
 if (!$export_to_csv) {
-    Display :: display_header(get_lang('Reporting'));
+    Display::display_header(get_lang('Reporting'));
     echo '<div class="actions" style ="font-size:10pt;">';
     if ($global) {
         echo '<div style="float:right"> <a href="'.api_get_self().'?export=1&score='.$filter_score.'&exercise_id='.$exercise_id.'">
@@ -244,9 +244,9 @@ function export_complete_report_csv($filename, $array)
     ];
     if (!empty($array)) {
         $array = array_merge($header, $array);
-        Export :: arrayToCsv($array, $filename);
+        Export::arrayToCsv($array, $filename);
     }
     exit;
 }
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/upload/upload_ppt.php b/main/upload/upload_ppt.php
index 1596d7e089..d54fc9aa77 100755
--- a/main/upload/upload_ppt.php
+++ b/main/upload/upload_ppt.php
@@ -73,7 +73,7 @@ if (!$is_allowed_to_edit) {
 $interbreadcrumb[] = ["url" => "../lp/lp_controller.php?action=list", "name" => get_lang("Doc")];
 
 $nameTools = get_lang("OogieConversionPowerPoint");
-Display :: display_header($nameTools);
+Display::display_header($nameTools);
 $message = get_lang("WelcomeOogieConverter");
 
 if (!empty($errorMessage)) {
diff --git a/main/upload/upload_word.php b/main/upload/upload_word.php
index 0e3c4459ff..4f4832952a 100755
--- a/main/upload/upload_word.php
+++ b/main/upload/upload_word.php
@@ -85,7 +85,7 @@ if (!$is_allowed_to_edit) {
 
 $interbreadcrumb[] = ["url" => "../lp/lp_controller.php?action=list", "name" => get_lang("Doc")];
 $nameTools = get_lang("WoogieConversionPowerPoint");
-Display :: display_header($nameTools);
+Display::display_header($nameTools);
 
 echo '<span style="color: #5577af; font-size: 16px; font-family: Arial; margin-left: 10px;">'.
     get_lang("WelcomeWoogieSubtitle").'</span><br>';
diff --git a/main/user/add_users_to_session.php b/main/user/add_users_to_session.php
index 6e1e70b117..a7b855eb9b 100755
--- a/main/user/add_users_to_session.php
+++ b/main/user/add_users_to_session.php
@@ -203,7 +203,7 @@ if ($allowTutors == 'true') {
                 $xajax_response->addAssign('ajax_list_users_single', 'innerHTML', api_utf8_encode($return));
             } else {
                 $return .= '<select id="origin_users" name="nosessionUsersList[]" multiple="multiple" size="15" style="width:360px;">';
-                while ($user = Database :: fetch_array($rs)) {
+                while ($user = Database::fetch_array($rs)) {
                     $person_name = api_get_person_name($user['firstname'], $user['lastname']);
                     $return .= '<option value="'.$user['user_id'].'">'.$person_name.' ('.$user['username'].')</option>';
                 }
@@ -525,7 +525,7 @@ if ($allowTutors == 'true') {
                     <select id="first_letter_user" name="firstLetterUser" onchange = "change_select(this.value);" >
                     <option value = "%">--</option>
                     <?php
-                        echo Display :: get_alphabet_options(); ?>
+                        echo Display::get_alphabet_options(); ?>
                     </select>
             <?php
     } ?>
diff --git a/main/user/subscribe_user.php b/main/user/subscribe_user.php
index d5dbcf6bfd..2c527d2ef0 100755
--- a/main/user/subscribe_user.php
+++ b/main/user/subscribe_user.php
@@ -166,7 +166,7 @@ if (!empty($_POST['keyword'])) {
     echo '<br/>'.get_lang('SearchResultsFor').' <span style="font-style: italic ;"> '.$keyword_name.' </span><br>';
 }
 
-Display :: display_header($tool_name, 'User');
+Display::display_header($tool_name, 'User');
 
 // Build search-form
 switch ($type) {
@@ -381,12 +381,12 @@ function get_number_of_users()
 
         // getting all the users of the course (to make sure that we do not display users that are already in the course)
         if (!empty($sessionId)) {
-            $a_course_users = CourseManager:: get_user_list_from_course_code(
+            $a_course_users = CourseManager::get_user_list_from_course_code(
                 $courseCode,
                 $sessionId
             );
         } else {
-            $a_course_users = CourseManager:: get_user_list_from_course_code(
+            $a_course_users = CourseManager::get_user_list_from_course_code(
                 $courseCode,
                 0
             );
@@ -649,9 +649,9 @@ function get_user_data($from, $number_of_items, $column, $direction)
         // getting all the users of the course (to make sure that we do not
         // display users that are already in the course)
         if (!empty($sessionId)) {
-            $a_course_users = CourseManager :: get_user_list_from_course_code($course_code, $sessionId);
+            $a_course_users = CourseManager::get_user_list_from_course_code($course_code, $sessionId);
         } else {
-            $a_course_users = CourseManager :: get_user_list_from_course_code($course_code, 0);
+            $a_course_users = CourseManager::get_user_list_from_course_code($course_code, 0);
         }
         foreach ($a_course_users as $user_id => $course_user) {
             $users_of_course[] = $course_user['user_id'];
@@ -684,7 +684,7 @@ function get_user_data($from, $number_of_items, $column, $direction)
  */
 function email_filter($email)
 {
-    return Display :: encrypted_mailto_link($email, $email);
+    return Display::encrypted_mailto_link($email, $email);
 }
 /**
  * Build the reg-column of the table.
diff --git a/main/user/user.php b/main/user/user.php
index 185f4dd825..2184398d3d 100755
--- a/main/user/user.php
+++ b/main/user/user.php
@@ -247,7 +247,7 @@ if (isset($_GET['action'])) {
                 $rs = Database::query($sql);
                 $counter = 1;
 
-                while ($user = Database:: fetch_array($rs, 'ASSOC')) {
+                while ($user = Database::fetch_array($rs, 'ASSOC')) {
                     if (isset($user['legal_agreement'])) {
                         if ($user['legal_agreement'] == 1) {
                             $user['legal_agreement'] = get_lang('Yes');
@@ -836,7 +836,7 @@ function get_user_data($from, $number_of_items, $column, $direction)
         }
     }
 
-    $users = CourseManager :: get_user_list_from_course_code(
+    $users = CourseManager::get_user_list_from_course_code(
         $course_code,
         $sessionId,
         $limit,
diff --git a/main/user/user_export.php b/main/user/user_export.php
index f2a9d914a6..f9efe4eec9 100644
--- a/main/user/user_export.php
+++ b/main/user/user_export.php
@@ -156,7 +156,7 @@ if ($export['addcsvheader'] == '1' && $export['file_type'] === 'csv') {
 
 $res = Database::query($sql);
 while ($user = Database::fetch_array($res, 'ASSOC')) {
-    $studentData = UserManager:: get_extra_user_data(
+    $studentData = UserManager::get_extra_user_data(
         $user['UserId'],
         true,
         false
diff --git a/main/webservices/registration.soap.php b/main/webservices/registration.soap.php
index e89eb90f6d..2a1c52ba23 100755
--- a/main/webservices/registration.soap.php
+++ b/main/webservices/registration.soap.php
@@ -3250,7 +3250,7 @@ function WSCreateCourseByTitle($params)
 
         $keys = AddCourse::define_course_keys($wanted_code, '', $_configuration['db_prefix']);
 
-        $sql_check = sprintf('SELECT * FROM '.$table_course.' WHERE visual_code = "%s"', Database :: escape_string($wanted_code));
+        $sql_check = sprintf('SELECT * FROM '.$table_course.' WHERE visual_code = "%s"', Database::escape_string($wanted_code));
         $result_check = Database::query($sql_check); // I don't know why this api function doesn't work...
         if (Database::num_rows($result_check) < 1) {
             $params = [];
diff --git a/main/webservices/user_import/import.lib.php b/main/webservices/user_import/import.lib.php
index 066bd5b78d..f41bb23d03 100755
--- a/main/webservices/user_import/import.lib.php
+++ b/main/webservices/user_import/import.lib.php
@@ -98,7 +98,7 @@ function save_data($users)
         foreach ($users as $index => $user) {
             $user = complete_missing_data($user);
             $user['Status'] = api_status_key($user['Status']);
-            $user_id = UserManager:: create_user(
+            $user_id = UserManager::create_user(
                 $user['FirstName'],
                 $user['LastName'],
                 $user['Status'],
diff --git a/main/work/edit_work.php b/main/work/edit_work.php
index 82ee17a381..cebe8815cf 100755
--- a/main/work/edit_work.php
+++ b/main/work/edit_work.php
@@ -142,4 +142,4 @@ Display::display_header();
 
 $form->display();
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/work/student_work.php b/main/work/student_work.php
index c282366551..0f19ed3ba8 100755
--- a/main/work/student_work.php
+++ b/main/work/student_work.php
@@ -82,7 +82,7 @@ $interbreadcrumb[] = [
     'name' => $userInfo['complete_name'],
 ];
 
-Display :: display_header(null);
+Display::display_header(null);
 
 $workPerUser = getWorkPerUser($studentId);
 
@@ -174,4 +174,4 @@ foreach ($workPerUser as $work) {
 echo Display::page_subheader($userInfo['complete_name']);
 echo $table->toHtml();
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/work/upload.php b/main/work/upload.php
index 3ea7fab41c..9705186355 100755
--- a/main/work/upload.php
+++ b/main/work/upload.php
@@ -163,4 +163,4 @@ if (!empty($work_id)) {
     Display::addFlash(Display::return_message(get_lang('ActionNotAllowed'), 'error'));
 }
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/work/upload_corrections.php b/main/work/upload_corrections.php
index 85cbab7907..9d4ff065ae 100644
--- a/main/work/upload_corrections.php
+++ b/main/work/upload_corrections.php
@@ -198,7 +198,7 @@ if ($form->validate()) {
 }
 
 $htmlHeadXtra[] = to_javascript_work();
-Display :: display_header(null);
+Display::display_header(null);
 
 if (!empty($workId)) {
     echo $validationStatus['message'];
@@ -211,4 +211,4 @@ if (!empty($workId)) {
     api_not_allowed();
 }
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/work/upload_from_template.php b/main/work/upload_from_template.php
index b7b1108ff4..cd228b23da 100755
--- a/main/work/upload_from_template.php
+++ b/main/work/upload_from_template.php
@@ -114,7 +114,7 @@ if ($form->validate()) {
 }
 
 $htmlHeadXtra[] = to_javascript_work();
-Display :: display_header(null);
+Display::display_header(null);
 
 if (!empty($work_id)) {
     echo $validationStatus['message'];
@@ -133,4 +133,4 @@ if (!empty($work_id)) {
     api_not_allowed();
 }
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/main/work/work.lib.php b/main/work/work.lib.php
index ab5692d35c..559bc1bcbf 100755
--- a/main/work/work.lib.php
+++ b/main/work/work.lib.php
@@ -4531,7 +4531,7 @@ function uploadWork($my_folder_data, $_course, $isCorrection = false, $workInfo
 
     if (empty($file['size'])) {
         return [
-            'error' => Display:: return_message(
+            'error' => Display::return_message(
                 get_lang('UplUploadFailedSizeIsZero'),
                 'error'
             ),
@@ -4604,7 +4604,7 @@ function uploadWork($my_folder_data, $_course, $isCorrection = false, $workInfo
         }
     } else {
         return [
-            'error' => Display :: return_message(
+            'error' => Display::return_message(
                 get_lang('FolderDoesntExistsInFileSystem'),
                 'error'
             ),
diff --git a/main/work/work_list.php b/main/work/work_list.php
index 588b05770b..f363c2d2ab 100755
--- a/main/work/work_list.php
+++ b/main/work/work_list.php
@@ -43,7 +43,7 @@ $htmlHeadXtra[] = api_get_jqgrid_js();
 $url_dir = api_get_path(WEB_CODE_PATH).'work/work.php?'.api_get_cidreq();
 
 if (!empty($group_id)) {
-    $group_properties = GroupManager :: get_group_properties($group_id);
+    $group_properties = GroupManager::get_group_properties($group_id);
     $interbreadcrumb[] = [
         'url' => api_get_path(WEB_CODE_PATH).'group/group.php?'.api_get_cidreq(),
         'name' => get_lang('Groups'),
diff --git a/main/work/work_list_all.php b/main/work/work_list_all.php
index cb9e494eb3..794b9b3dc4 100755
--- a/main/work/work_list_all.php
+++ b/main/work/work_list_all.php
@@ -478,7 +478,7 @@ if ($allowAntiPlagiarism) {
     Display::panel($table);
     echo '</div>';
 
-    $workTable = Database:: get_course_table(TABLE_STUDENT_PUBLICATION);
+    $workTable = Database::get_course_table(TABLE_STUDENT_PUBLICATION);
     $courseId = $courseInfo['real_id'];
     $formAction['analyseCompilatio'] = [
         'label' => get_lang('CompilatioStartAnalysis'),
diff --git a/main/work/work_list_others.php b/main/work/work_list_others.php
index c65ff96ee8..59abbe2ca3 100755
--- a/main/work/work_list_others.php
+++ b/main/work/work_list_others.php
@@ -74,7 +74,7 @@ $interbreadcrumb[] = [
     'name' => $my_folder_data['title'],
 ];
 
-Display :: display_header(null);
+Display::display_header(null);
 
 echo '<div class="actions">';
 echo '<a href="'.api_get_path(WEB_CODE_PATH).'work/work.php?'.api_get_cidreq().'>'.
@@ -214,4 +214,4 @@ $url = api_get_path(WEB_AJAX_PATH).'model.ajax.php?a=get_work_user_list_others&w
 <?php
 echo Display::grid_html('results');
 
-Display :: display_footer();
+Display::display_footer();
diff --git a/plugin/azure_active_directory/src/AzureActiveDirectory.php b/plugin/azure_active_directory/src/AzureActiveDirectory.php
index 6c6eb10a8d..8e0f33f3d3 100644
--- a/plugin/azure_active_directory/src/AzureActiveDirectory.php
+++ b/plugin/azure_active_directory/src/AzureActiveDirectory.php
@@ -12,23 +12,23 @@ use TheNetworg\OAuth2\Client\Provider\Azure;
  */
 class AzureActiveDirectory extends Plugin
 {
-    const SETTING_ENABLE = 'enable';
-    const SETTING_APP_ID = 'app_id';
-    const SETTING_APP_SECRET = 'app_secret';
-    const SETTING_BLOCK_NAME = 'block_name';
-    const SETTING_FORCE_LOGOUT_BUTTON = 'force_logout';
-    const SETTING_MANAGEMENT_LOGIN_ENABLE = 'management_login_enable';
-    const SETTING_MANAGEMENT_LOGIN_NAME = 'management_login_name';
-    const SETTING_PROVISION_USERS = 'provisioning';
-    const SETTING_GROUP_ID_ADMIN = 'group_id_admin';
-    const SETTING_GROUP_ID_SESSION_ADMIN = 'group_id_session_admin';
-    const SETTING_GROUP_ID_TEACHER = 'group_id_teacher';
+    public const SETTING_ENABLE = 'enable';
+    public const SETTING_APP_ID = 'app_id';
+    public const SETTING_APP_SECRET = 'app_secret';
+    public const SETTING_BLOCK_NAME = 'block_name';
+    public const SETTING_FORCE_LOGOUT_BUTTON = 'force_logout';
+    public const SETTING_MANAGEMENT_LOGIN_ENABLE = 'management_login_enable';
+    public const SETTING_MANAGEMENT_LOGIN_NAME = 'management_login_name';
+    public const SETTING_PROVISION_USERS = 'provisioning';
+    public const SETTING_GROUP_ID_ADMIN = 'group_id_admin';
+    public const SETTING_GROUP_ID_SESSION_ADMIN = 'group_id_session_admin';
+    public const SETTING_GROUP_ID_TEACHER = 'group_id_teacher';
 
-    const URL_TYPE_AUTHORIZE = 'login';
-    const URL_TYPE_LOGOUT = 'logout';
+    public const URL_TYPE_AUTHORIZE = 'login';
+    public const URL_TYPE_LOGOUT = 'logout';
 
-    const EXTRA_FIELD_ORGANISATION_EMAIL = 'organisationemail';
-    const EXTRA_FIELD_AZURE_ID = 'azure_id';
+    public const EXTRA_FIELD_ORGANISATION_EMAIL = 'organisationemail';
+    public const EXTRA_FIELD_AZURE_ID = 'azure_id';
 
     /**
      * AzureActiveDirectory constructor.
diff --git a/plugin/buycourses/src/buy_course_plugin.class.php b/plugin/buycourses/src/buy_course_plugin.class.php
index 6ed880fad8..80502c343c 100644
--- a/plugin/buycourses/src/buy_course_plugin.class.php
+++ b/plugin/buycourses/src/buy_course_plugin.class.php
@@ -20,58 +20,58 @@ use Symfony\Component\HttpFoundation\Request as HttpRequest;
  */
 class BuyCoursesPlugin extends Plugin
 {
-    const TABLE_PAYPAL = 'plugin_buycourses_paypal_account';
-    const TABLE_CURRENCY = 'plugin_buycourses_currency';
-    const TABLE_ITEM = 'plugin_buycourses_item';
-    const TABLE_ITEM_BENEFICIARY = 'plugin_buycourses_item_rel_beneficiary';
-    const TABLE_SALE = 'plugin_buycourses_sale';
-    const TABLE_TRANSFER = 'plugin_buycourses_transfer';
-    const TABLE_COMMISSION = 'plugin_buycourses_commission';
-    const TABLE_PAYPAL_PAYOUTS = 'plugin_buycourses_paypal_payouts';
-    const TABLE_SERVICES = 'plugin_buycourses_services';
-    const TABLE_SERVICES_SALE = 'plugin_buycourses_service_sale';
-    const TABLE_CULQI = 'plugin_buycourses_culqi';
-    const TABLE_GLOBAL_CONFIG = 'plugin_buycourses_global_config';
-    const TABLE_INVOICE = 'plugin_buycourses_invoices';
-    const TABLE_TPV_REDSYS = 'plugin_buycourses_tpvredsys_account';
-    const TABLE_COUPON = 'plugin_buycourses_coupon';
-    const TABLE_COUPON_ITEM = 'plugin_buycourses_coupon_rel_item';
-    const TABLE_COUPON_SERVICE = 'plugin_buycourses_coupon_rel_service';
-    const TABLE_COUPON_SALE = 'plugin_buycourses_coupon_rel_sale';
-    const TABLE_COUPON_SERVICE_SALE = 'plugin_buycourses_coupon_rel_service_sale';
-    const TABLE_STRIPE = 'plugin_buycourses_stripe_account';
-    const PRODUCT_TYPE_COURSE = 1;
-    const PRODUCT_TYPE_SESSION = 2;
-    const PRODUCT_TYPE_SERVICE = 3;
-    const PAYMENT_TYPE_PAYPAL = 1;
-    const PAYMENT_TYPE_TRANSFER = 2;
-    const PAYMENT_TYPE_CULQI = 3;
-    const PAYMENT_TYPE_TPV_REDSYS = 4;
-    const PAYMENT_TYPE_STRIPE = 5;
-    const PAYOUT_STATUS_CANCELED = 2;
-    const PAYOUT_STATUS_PENDING = 0;
-    const PAYOUT_STATUS_COMPLETED = 1;
-    const SALE_STATUS_CANCELED = -1;
-    const SALE_STATUS_PENDING = 0;
-    const SALE_STATUS_COMPLETED = 1;
-    const SERVICE_STATUS_PENDING = 0;
-    const SERVICE_STATUS_COMPLETED = 1;
-    const SERVICE_STATUS_CANCELLED = -1;
-    const SERVICE_TYPE_USER = 1;
-    const SERVICE_TYPE_COURSE = 2;
-    const SERVICE_TYPE_SESSION = 3;
-    const SERVICE_TYPE_LP_FINAL_ITEM = 4;
-    const CULQI_INTEGRATION_TYPE = 'INTEG';
-    const CULQI_PRODUCTION_TYPE = 'PRODUC';
-    const TAX_APPLIES_TO_ALL = 1;
-    const TAX_APPLIES_TO_ONLY_COURSE = 2;
-    const TAX_APPLIES_TO_ONLY_SESSION = 3;
-    const TAX_APPLIES_TO_ONLY_SERVICES = 4;
-    const PAGINATION_PAGE_SIZE = 6;
-    const COUPON_DISCOUNT_TYPE_PERCENTAGE = 1;
-    const COUPON_DISCOUNT_TYPE_AMOUNT = 2;
-    const COUPON_STATUS_ACTIVE = 1;
-    const COUPON_STATUS_DISABLE = 0;
+    public const TABLE_PAYPAL = 'plugin_buycourses_paypal_account';
+    public const TABLE_CURRENCY = 'plugin_buycourses_currency';
+    public const TABLE_ITEM = 'plugin_buycourses_item';
+    public const TABLE_ITEM_BENEFICIARY = 'plugin_buycourses_item_rel_beneficiary';
+    public const TABLE_SALE = 'plugin_buycourses_sale';
+    public const TABLE_TRANSFER = 'plugin_buycourses_transfer';
+    public const TABLE_COMMISSION = 'plugin_buycourses_commission';
+    public const TABLE_PAYPAL_PAYOUTS = 'plugin_buycourses_paypal_payouts';
+    public const TABLE_SERVICES = 'plugin_buycourses_services';
+    public const TABLE_SERVICES_SALE = 'plugin_buycourses_service_sale';
+    public const TABLE_CULQI = 'plugin_buycourses_culqi';
+    public const TABLE_GLOBAL_CONFIG = 'plugin_buycourses_global_config';
+    public const TABLE_INVOICE = 'plugin_buycourses_invoices';
+    public const TABLE_TPV_REDSYS = 'plugin_buycourses_tpvredsys_account';
+    public const TABLE_COUPON = 'plugin_buycourses_coupon';
+    public const TABLE_COUPON_ITEM = 'plugin_buycourses_coupon_rel_item';
+    public const TABLE_COUPON_SERVICE = 'plugin_buycourses_coupon_rel_service';
+    public const TABLE_COUPON_SALE = 'plugin_buycourses_coupon_rel_sale';
+    public const TABLE_COUPON_SERVICE_SALE = 'plugin_buycourses_coupon_rel_service_sale';
+    public const TABLE_STRIPE = 'plugin_buycourses_stripe_account';
+    public const PRODUCT_TYPE_COURSE = 1;
+    public const PRODUCT_TYPE_SESSION = 2;
+    public const PRODUCT_TYPE_SERVICE = 3;
+    public const PAYMENT_TYPE_PAYPAL = 1;
+    public const PAYMENT_TYPE_TRANSFER = 2;
+    public const PAYMENT_TYPE_CULQI = 3;
+    public const PAYMENT_TYPE_TPV_REDSYS = 4;
+    public const PAYMENT_TYPE_STRIPE = 5;
+    public const PAYOUT_STATUS_CANCELED = 2;
+    public const PAYOUT_STATUS_PENDING = 0;
+    public const PAYOUT_STATUS_COMPLETED = 1;
+    public const SALE_STATUS_CANCELED = -1;
+    public const SALE_STATUS_PENDING = 0;
+    public const SALE_STATUS_COMPLETED = 1;
+    public const SERVICE_STATUS_PENDING = 0;
+    public const SERVICE_STATUS_COMPLETED = 1;
+    public const SERVICE_STATUS_CANCELLED = -1;
+    public const SERVICE_TYPE_USER = 1;
+    public const SERVICE_TYPE_COURSE = 2;
+    public const SERVICE_TYPE_SESSION = 3;
+    public const SERVICE_TYPE_LP_FINAL_ITEM = 4;
+    public const CULQI_INTEGRATION_TYPE = 'INTEG';
+    public const CULQI_PRODUCTION_TYPE = 'PRODUC';
+    public const TAX_APPLIES_TO_ALL = 1;
+    public const TAX_APPLIES_TO_ONLY_COURSE = 2;
+    public const TAX_APPLIES_TO_ONLY_SESSION = 3;
+    public const TAX_APPLIES_TO_ONLY_SERVICES = 4;
+    public const PAGINATION_PAGE_SIZE = 6;
+    public const COUPON_DISCOUNT_TYPE_PERCENTAGE = 1;
+    public const COUPON_DISCOUNT_TYPE_AMOUNT = 2;
+    public const COUPON_STATUS_ACTIVE = 1;
+    public const COUPON_STATUS_DISABLE = 0;
 
     public $isAdminPlugin = true;
 
diff --git a/plugin/coursehomenotify/CourseHomeNotifyPlugin.php b/plugin/coursehomenotify/CourseHomeNotifyPlugin.php
index 2429756e27..2eedb8f160 100644
--- a/plugin/coursehomenotify/CourseHomeNotifyPlugin.php
+++ b/plugin/coursehomenotify/CourseHomeNotifyPlugin.php
@@ -10,7 +10,7 @@ use Doctrine\ORM\Tools\SchemaTool;
  */
 class CourseHomeNotifyPlugin extends Plugin
 {
-    const SETTING_ENABLED = 'enabled';
+    public const SETTING_ENABLED = 'enabled';
 
     /**
      * CourseHomeNotifyPlugin constructor.
diff --git a/plugin/createdrupaluser/src/CreateDrupalUser.php b/plugin/createdrupaluser/src/CreateDrupalUser.php
index 476037e908..bf7a14a6fc 100644
--- a/plugin/createdrupaluser/src/CreateDrupalUser.php
+++ b/plugin/createdrupaluser/src/CreateDrupalUser.php
@@ -10,7 +10,7 @@
  */
 class CreateDrupalUser extends Plugin implements HookPluginInterface
 {
-    const EXTRAFIELD_VARIABLE_NAME = 'drupal_user_id';
+    public const EXTRAFIELD_VARIABLE_NAME = 'drupal_user_id';
 
     /**
      * Class constructor.
diff --git a/plugin/customcertificate/src/CustomCertificatePlugin.php b/plugin/customcertificate/src/CustomCertificatePlugin.php
index 37f323044c..9f5c5e70cb 100644
--- a/plugin/customcertificate/src/CustomCertificatePlugin.php
+++ b/plugin/customcertificate/src/CustomCertificatePlugin.php
@@ -10,7 +10,7 @@
  */
 class CustomCertificatePlugin extends Plugin
 {
-    const TABLE_CUSTOMCERTIFICATE = 'plugin_customcertificate';
+    public const TABLE_CUSTOMCERTIFICATE = 'plugin_customcertificate';
     public $isCoursePlugin = true;
 
     // When creating a new course this settings are added to the course
diff --git a/plugin/embedregistry/EmbedRegistryPlugin.php b/plugin/embedregistry/EmbedRegistryPlugin.php
index cc90b8610b..d79a64e32e 100644
--- a/plugin/embedregistry/EmbedRegistryPlugin.php
+++ b/plugin/embedregistry/EmbedRegistryPlugin.php
@@ -11,10 +11,10 @@ use Doctrine\ORM\Tools\SchemaTool;
  */
 class EmbedRegistryPlugin extends Plugin
 {
-    const SETTING_ENABLED = 'tool_enabled';
-    const SETTING_TITLE = 'tool_title';
-    const SETTING_EXTERNAL_URL = 'external_url';
-    const TBL_EMBED = 'plugin_embed_registry_embed';
+    public const SETTING_ENABLED = 'tool_enabled';
+    public const SETTING_TITLE = 'tool_title';
+    public const SETTING_EXTERNAL_URL = 'external_url';
+    public const TBL_EMBED = 'plugin_embed_registry_embed';
 
     /**
      * EmbedRegistryPlugin constructor.
diff --git a/plugin/google_meet/src/google_meet_plugin.class.php b/plugin/google_meet/src/google_meet_plugin.class.php
index da2301219e..be87472b9c 100644
--- a/plugin/google_meet/src/google_meet_plugin.class.php
+++ b/plugin/google_meet/src/google_meet_plugin.class.php
@@ -9,10 +9,10 @@
  */
 class GoogleMeetPlugin extends Plugin
 {
-    const TABLE_MEET_LIST = 'plugin_google_meet_room';
-    const SETTING_TITLE = 'tool_title';
-    const SETTING_ENABLED = 'google_meet_enabled';
-    const GOOGLE_MEET_URL = 'https://meet.google.com/';
+    public const TABLE_MEET_LIST = 'plugin_google_meet_room';
+    public const SETTING_TITLE = 'tool_title';
+    public const SETTING_ENABLED = 'google_meet_enabled';
+    public const GOOGLE_MEET_URL = 'https://meet.google.com/';
 
     public $isCoursePlugin = true;
 
diff --git a/plugin/grading_electronic/src/GradingElectronicPlugin.php b/plugin/grading_electronic/src/GradingElectronicPlugin.php
index 1fa3524385..5412d74c03 100644
--- a/plugin/grading_electronic/src/GradingElectronicPlugin.php
+++ b/plugin/grading_electronic/src/GradingElectronicPlugin.php
@@ -6,10 +6,10 @@
  */
 class GradingElectronicPlugin extends Plugin
 {
-    const EXTRAFIELD_STUDENT_ID = 'fcdice_or_acadis_student_id';
-    const EXTRAFIELD_COURSE_PROVIDER_ID = 'plugin_gradingelectronic_provider_id';
-    const EXTRAFIELD_COURSE_ID = 'plugin_gradingelectronic_course_id';
-    const EXTRAFIELD_COURSE_HOURS = 'plugin_gradingelectronic_coursehours';
+    public const EXTRAFIELD_STUDENT_ID = 'fcdice_or_acadis_student_id';
+    public const EXTRAFIELD_COURSE_PROVIDER_ID = 'plugin_gradingelectronic_provider_id';
+    public const EXTRAFIELD_COURSE_ID = 'plugin_gradingelectronic_course_id';
+    public const EXTRAFIELD_COURSE_HOURS = 'plugin_gradingelectronic_coursehours';
 
     /**
      * {@inheritdoc}
diff --git a/plugin/learning_calendar/LearningCalendarPlugin.php b/plugin/learning_calendar/LearningCalendarPlugin.php
index 9c81076145..e1397a12d2 100644
--- a/plugin/learning_calendar/LearningCalendarPlugin.php
+++ b/plugin/learning_calendar/LearningCalendarPlugin.php
@@ -6,9 +6,9 @@
  */
 class LearningCalendarPlugin extends Plugin
 {
-    const EVENT_TYPE_TAKEN = 1;
-    const EVENT_TYPE_EXAM = 2;
-    const EVENT_TYPE_FREE = 3;
+    public const EVENT_TYPE_TAKEN = 1;
+    public const EVENT_TYPE_EXAM = 2;
+    public const EVENT_TYPE_FREE = 3;
 
     /**
      * Class constructor.
diff --git a/plugin/lti_provider/LtiProviderPlugin.php b/plugin/lti_provider/LtiProviderPlugin.php
index a2e1d4d549..591cd2ea2a 100644
--- a/plugin/lti_provider/LtiProviderPlugin.php
+++ b/plugin/lti_provider/LtiProviderPlugin.php
@@ -13,7 +13,7 @@ use Doctrine\ORM\Tools\SchemaTool;
  */
 class LtiProviderPlugin extends Plugin
 {
-    const TABLE_PLATFORM = 'plugin_lti_provider_platform';
+    public const TABLE_PLATFORM = 'plugin_lti_provider_platform';
 
     public $isAdminPlugin = true;
 
diff --git a/plugin/migrationmoodle/src/Loader/CoursesLoader.php b/plugin/migrationmoodle/src/Loader/CoursesLoader.php
index 980e755010..346f371d56 100644
--- a/plugin/migrationmoodle/src/Loader/CoursesLoader.php
+++ b/plugin/migrationmoodle/src/Loader/CoursesLoader.php
@@ -12,8 +12,8 @@ use Chamilo\PluginBundle\MigrationMoodle\Interfaces\LoaderInterface;
  */
 class CoursesLoader implements LoaderInterface
 {
-    const LOAD_MODE_REUSE = 'reuse';
-    const LOAD_MODE_DUPLICATE = 'duplicate';
+    public const LOAD_MODE_REUSE = 'reuse';
+    public const LOAD_MODE_DUPLICATE = 'duplicate';
 
     /**
      * @var string Load mode: "reuse" or "duplicate". Default is "duplicate".
diff --git a/plugin/migrationmoodle/src/Loader/LessonAnswersShortAnswerLoader.php b/plugin/migrationmoodle/src/Loader/LessonAnswersShortAnswerLoader.php
index 89e3456fed..ddb8b361a6 100644
--- a/plugin/migrationmoodle/src/Loader/LessonAnswersShortAnswerLoader.php
+++ b/plugin/migrationmoodle/src/Loader/LessonAnswersShortAnswerLoader.php
@@ -14,7 +14,7 @@ use Chamilo\PluginBundle\MigrationMoodle\Interfaces\LoaderInterface;
  */
 class LessonAnswersShortAnswerLoader implements LoaderInterface
 {
-    const INPUT_WIDTH = 300;
+    public const INPUT_WIDTH = 300;
 
     /**
      * Load the data and return the ID inserted.
diff --git a/plugin/migrationmoodle/src/Loader/UserSessionLoader.php b/plugin/migrationmoodle/src/Loader/UserSessionLoader.php
index ca6da4ac2d..d617d136d4 100644
--- a/plugin/migrationmoodle/src/Loader/UserSessionLoader.php
+++ b/plugin/migrationmoodle/src/Loader/UserSessionLoader.php
@@ -12,8 +12,8 @@ use Chamilo\PluginBundle\MigrationMoodle\Interfaces\LoaderInterface;
  */
 class UserSessionLoader implements LoaderInterface
 {
-    const LOAD_MODE_REUSE = 'reuse';
-    const LOAD_MODE_DUPLICATE = 'duplicate';
+    public const LOAD_MODE_REUSE = 'reuse';
+    public const LOAD_MODE_DUPLICATE = 'duplicate';
 
     /**
      * @var string Load mode: "reuse" or "duplicate". Default is "duplicate".
diff --git a/plugin/migrationmoodle/src/Loader/UsersLoader.php b/plugin/migrationmoodle/src/Loader/UsersLoader.php
index 0f227f09bf..9bcf108e60 100644
--- a/plugin/migrationmoodle/src/Loader/UsersLoader.php
+++ b/plugin/migrationmoodle/src/Loader/UsersLoader.php
@@ -15,8 +15,8 @@ use Chamilo\UserBundle\Entity\User;
  */
 class UsersLoader implements LoaderInterface
 {
-    const LOAD_MODE_REUSE = 'reuse';
-    const LOAD_MODE_DUPLICATE = 'duplicate';
+    public const LOAD_MODE_REUSE = 'reuse';
+    public const LOAD_MODE_DUPLICATE = 'duplicate';
 
     /**
      * @var string Load mode: "reuse" or "duplicate". Default is "duplicate".
diff --git a/plugin/migrationmoodle/src/MigrationMoodlePlugin.php b/plugin/migrationmoodle/src/MigrationMoodlePlugin.php
index 66f35671f5..4ddfcf26ab 100644
--- a/plugin/migrationmoodle/src/MigrationMoodlePlugin.php
+++ b/plugin/migrationmoodle/src/MigrationMoodlePlugin.php
@@ -10,9 +10,9 @@ use Doctrine\DBAL\DriverManager;
  */
 class MigrationMoodlePlugin extends Plugin implements HookPluginInterface
 {
-    const SETTING_USER_FILTER = 'user_filter';
-    const SETTING_URL_ID = 'url_id';
-    const SETTING_MOODLE_PATH = 'moodle_path';
+    public const SETTING_USER_FILTER = 'user_filter';
+    public const SETTING_URL_ID = 'url_id';
+    public const SETTING_MOODLE_PATH = 'moodle_path';
 
     public $isAdminPlugin = true;
 
diff --git a/plugin/migrationmoodle/src/Task/LessonPagesTask.php b/plugin/migrationmoodle/src/Task/LessonPagesTask.php
index 972decc394..66a3da4db0 100644
--- a/plugin/migrationmoodle/src/Task/LessonPagesTask.php
+++ b/plugin/migrationmoodle/src/Task/LessonPagesTask.php
@@ -21,9 +21,9 @@ use Chamilo\PluginBundle\MigrationMoodle\Transformer\Property\LoadedLessonPageLo
  */
 class LessonPagesTask extends BaseTask
 {
-    const TYPE_END_BRANCH = 21;
-    const TYPE_CLUSTER = 30;
-    const TYPE_END_CLUSTER = 31;
+    public const TYPE_END_BRANCH = 21;
+    public const TYPE_CLUSTER = 30;
+    public const TYPE_END_CLUSTER = 31;
 
     /**
      * @return array
diff --git a/plugin/migrationmoodle/src/Task/RoleAssignmentsTask.php b/plugin/migrationmoodle/src/Task/RoleAssignmentsTask.php
index 24c56d9104..985c9138c4 100644
--- a/plugin/migrationmoodle/src/Task/RoleAssignmentsTask.php
+++ b/plugin/migrationmoodle/src/Task/RoleAssignmentsTask.php
@@ -18,7 +18,7 @@ use Chamilo\PluginBundle\MigrationMoodle\Transformer\Property\LoadedUserLookup;
  */
 class RoleAssignmentsTask extends BaseTask
 {
-    const CONTEXT_LEVEL_COURSE = 50;
+    public const CONTEXT_LEVEL_COURSE = 50;
 
     /**
      * @return array
diff --git a/plugin/migrationmoodle/src/Task/UserSessionsTask.php b/plugin/migrationmoodle/src/Task/UserSessionsTask.php
index 48ad6fb8f4..1651bdf92f 100644
--- a/plugin/migrationmoodle/src/Task/UserSessionsTask.php
+++ b/plugin/migrationmoodle/src/Task/UserSessionsTask.php
@@ -17,7 +17,7 @@ use Chamilo\PluginBundle\MigrationMoodle\Transformer\Property\SessionName;
  */
 class UserSessionsTask extends BaseTask
 {
-    const SEPARATOR_NAME = ' - ';
+    public const SEPARATOR_NAME = ' - ';
 
     /**
      * {@inheritdoc}
diff --git a/plugin/migrationmoodle/src/Transformer/Property/Explode.php b/plugin/migrationmoodle/src/Transformer/Property/Explode.php
index 2c16afc2b4..323178a064 100644
--- a/plugin/migrationmoodle/src/Transformer/Property/Explode.php
+++ b/plugin/migrationmoodle/src/Transformer/Property/Explode.php
@@ -12,7 +12,7 @@ use Chamilo\PluginBundle\MigrationMoodle\Interfaces\TransformPropertyInterface;
  */
 class Explode implements TransformPropertyInterface
 {
-    const SEPARATOR = '@mm@';
+    public const SEPARATOR = '@mm@';
 
     /**
      * @return mixed
diff --git a/plugin/migrationmoodle/src/Transformer/Property/UserStatus.php b/plugin/migrationmoodle/src/Transformer/Property/UserStatus.php
index 4156f79660..b404696563 100644
--- a/plugin/migrationmoodle/src/Transformer/Property/UserStatus.php
+++ b/plugin/migrationmoodle/src/Transformer/Property/UserStatus.php
@@ -15,7 +15,7 @@ use Doctrine\DBAL\FetchMode;
  */
 class UserStatus implements TransformPropertyInterface
 {
-    const ROLES = [
+    public const ROLES = [
         User::TEACHER => ['manager', 'coursecreator', 'editingteacher', 'teacher'],
         User::STUDENT => ['student', 'user'],
         INVITEE => ['guest'],
diff --git a/plugin/notebookteacher/src/NotebookTeacherPlugin.php b/plugin/notebookteacher/src/NotebookTeacherPlugin.php
index c54baf61f8..1b29a3ea28 100644
--- a/plugin/notebookteacher/src/NotebookTeacherPlugin.php
+++ b/plugin/notebookteacher/src/NotebookTeacherPlugin.php
@@ -11,7 +11,7 @@
  */
 class NotebookTeacherPlugin extends Plugin
 {
-    const TABLE_NOTEBOOKTEACHER = 'plugin_notebook_teacher';
+    public const TABLE_NOTEBOOKTEACHER = 'plugin_notebook_teacher';
     public $isCoursePlugin = true;
 
     /**
diff --git a/plugin/oauth2/src/OAuth2.php b/plugin/oauth2/src/OAuth2.php
index 1a96e6a0c4..4d482b3e58 100644
--- a/plugin/oauth2/src/OAuth2.php
+++ b/plugin/oauth2/src/OAuth2.php
@@ -19,46 +19,46 @@ class OAuth2 extends Plugin
 {
     use ArrayAccessorTrait;
 
-    const SETTING_ENABLE = 'enable';
+    public const SETTING_ENABLE = 'enable';
 
-    const SETTING_FORCE_REDIRECT = 'force_redirect';
-    const SETTING_SKIP_FORCE_REDIRECT_IN = 'skip_force_redirect_in';
+    public const SETTING_FORCE_REDIRECT = 'force_redirect';
+    public const SETTING_SKIP_FORCE_REDIRECT_IN = 'skip_force_redirect_in';
 
-    const SETTING_CLIENT_ID = 'client_id';
-    const SETTING_CLIENT_SECRET = 'client_secret';
+    public const SETTING_CLIENT_ID = 'client_id';
+    public const SETTING_CLIENT_SECRET = 'client_secret';
 
-    const SETTING_AUTHORIZE_URL = 'authorize_url';
-    const SETTING_SCOPES = 'scopes';
-    const SETTING_SCOPE_SEPARATOR = 'scope_separator';
+    public const SETTING_AUTHORIZE_URL = 'authorize_url';
+    public const SETTING_SCOPES = 'scopes';
+    public const SETTING_SCOPE_SEPARATOR = 'scope_separator';
 
-    const SETTING_ACCESS_TOKEN_URL = 'access_token_url';
-    const SETTING_ACCESS_TOKEN_METHOD = 'access_token_method';
+    public const SETTING_ACCESS_TOKEN_URL = 'access_token_url';
+    public const SETTING_ACCESS_TOKEN_METHOD = 'access_token_method';
     // const SETTING_ACCESS_TOKEN_RESOURCE_OWNER_ID = 'access_token_resource_owner_id';
 
-    const SETTING_RESOURCE_OWNER_DETAILS_URL = 'resource_owner_details_url';
+    public const SETTING_RESOURCE_OWNER_DETAILS_URL = 'resource_owner_details_url';
 
-    const SETTING_RESPONSE_ERROR = 'response_error';
-    const SETTING_RESPONSE_CODE = 'response_code';
-    const SETTING_RESPONSE_RESOURCE_OWNER_ID = 'response_resource_owner_id';
+    public const SETTING_RESPONSE_ERROR = 'response_error';
+    public const SETTING_RESPONSE_CODE = 'response_code';
+    public const SETTING_RESPONSE_RESOURCE_OWNER_ID = 'response_resource_owner_id';
 
-    const SETTING_UPDATE_USER_INFO = 'update_user_info';
-    const SETTING_CREATE_NEW_USERS = 'create_new_users';
-    const SETTING_RESPONSE_RESOURCE_OWNER_FIRSTNAME = 'response_resource_owner_firstname';
-    const SETTING_RESPONSE_RESOURCE_OWNER_LASTNAME = 'response_resource_owner_lastname';
-    const SETTING_RESPONSE_RESOURCE_OWNER_STATUS = 'response_resource_owner_status';
-    const SETTING_RESPONSE_RESOURCE_OWNER_EMAIL = 'response_resource_owner_email';
-    const SETTING_RESPONSE_RESOURCE_OWNER_USERNAME = 'response_resource_owner_username';
+    public const SETTING_UPDATE_USER_INFO = 'update_user_info';
+    public const SETTING_CREATE_NEW_USERS = 'create_new_users';
+    public const SETTING_RESPONSE_RESOURCE_OWNER_FIRSTNAME = 'response_resource_owner_firstname';
+    public const SETTING_RESPONSE_RESOURCE_OWNER_LASTNAME = 'response_resource_owner_lastname';
+    public const SETTING_RESPONSE_RESOURCE_OWNER_STATUS = 'response_resource_owner_status';
+    public const SETTING_RESPONSE_RESOURCE_OWNER_EMAIL = 'response_resource_owner_email';
+    public const SETTING_RESPONSE_RESOURCE_OWNER_USERNAME = 'response_resource_owner_username';
 
-    const SETTING_RESPONSE_RESOURCE_OWNER_URLS = 'response_resource_owner_urls';
+    public const SETTING_RESPONSE_RESOURCE_OWNER_URLS = 'response_resource_owner_urls';
 
-    const SETTING_LOGOUT_URL = 'logout_url';
+    public const SETTING_LOGOUT_URL = 'logout_url';
 
-    const SETTING_BLOCK_NAME = 'block_name';
+    public const SETTING_BLOCK_NAME = 'block_name';
 
-    const SETTING_MANAGEMENT_LOGIN_ENABLE = 'management_login_enable';
-    const SETTING_MANAGEMENT_LOGIN_NAME = 'management_login_name';
+    public const SETTING_MANAGEMENT_LOGIN_ENABLE = 'management_login_enable';
+    public const SETTING_MANAGEMENT_LOGIN_NAME = 'management_login_name';
 
-    const EXTRA_FIELD_OAUTH2_ID = 'oauth2_id';
+    public const EXTRA_FIELD_OAUTH2_ID = 'oauth2_id';
 
     protected function __construct()
     {
diff --git a/plugin/pens/chamilo_pens.php b/plugin/pens/chamilo_pens.php
index a99a12c247..5ce01f411d 100755
--- a/plugin/pens/chamilo_pens.php
+++ b/plugin/pens/chamilo_pens.php
@@ -26,7 +26,7 @@ class ChamiloPens extends Plugin
     /**
      * Database table to be used.
      */
-    const TABLE_NAME = "plugin_pens";
+    public const TABLE_NAME = "plugin_pens";
 
     /**
      * Id of the object.
diff --git a/plugin/questionoptionsevaluation/QuestionOptionsEvaluationPlugin.php b/plugin/questionoptionsevaluation/QuestionOptionsEvaluationPlugin.php
index 508824e149..716d9098b6 100644
--- a/plugin/questionoptionsevaluation/QuestionOptionsEvaluationPlugin.php
+++ b/plugin/questionoptionsevaluation/QuestionOptionsEvaluationPlugin.php
@@ -8,9 +8,9 @@ use Chamilo\CoreBundle\Entity\TrackEAttempt;
  */
 class QuestionOptionsEvaluationPlugin extends Plugin
 {
-    const SETTING_ENABLE = 'enable';
-    const SETTING_MAX_SCORE = 'exercise_max_score';
-    const EXTRAFIELD_FORMULA = 'quiz_evaluation_formula';
+    public const SETTING_ENABLE = 'enable';
+    public const SETTING_MAX_SCORE = 'exercise_max_score';
+    public const EXTRAFIELD_FORMULA = 'quiz_evaluation_formula';
 
     /**
      * QuestionValuationPlugin constructor.
diff --git a/plugin/remedial_course/RemedialCoursePlugin.php b/plugin/remedial_course/RemedialCoursePlugin.php
index 4ef45d2ec0..6add9266d4 100644
--- a/plugin/remedial_course/RemedialCoursePlugin.php
+++ b/plugin/remedial_course/RemedialCoursePlugin.php
@@ -7,9 +7,9 @@
  */
 class RemedialCoursePlugin extends Plugin
 {
-    const SETTING_ENABLED = 'enabled';
-    const EXTRAFIELD_REMEDIAL_VARIABLE = 'remedialcourselist';
-    const EXTRAFIELD_ADVACED_VARIABLE = 'advancedcourselist';
+    public const SETTING_ENABLED = 'enabled';
+    public const EXTRAFIELD_REMEDIAL_VARIABLE = 'remedialcourselist';
+    public const EXTRAFIELD_ADVACED_VARIABLE = 'advancedcourselist';
 
     /**
      * RemedialCoursePlugin constructor.
diff --git a/plugin/search_course/lib/register_course_widget.class.php b/plugin/search_course/lib/register_course_widget.class.php
index 4a7e0cee82..5fcb48cea9 100755
--- a/plugin/search_course/lib/register_course_widget.class.php
+++ b/plugin/search_course/lib/register_course_widget.class.php
@@ -11,9 +11,9 @@
  */
 class RegisterCourseWidget
 {
-    const ACTION_SUBSCRIBE = 'subscribe';
-    const PARAM_SUBSCRIBE = 'subscribe';
-    const PARAM_PASSCODE = 'course_registration_code';
+    public const ACTION_SUBSCRIBE = 'subscribe';
+    public const PARAM_SUBSCRIBE = 'subscribe';
+    public const PARAM_PASSCODE = 'course_registration_code';
 
     /**
      * Returns $_POST data for $key is it exists or $default otherwise.
diff --git a/plugin/search_course/lib/search_course_widget.class.php b/plugin/search_course/lib/search_course_widget.class.php
index 7a3b7c4d0e..ae85e3041e 100755
--- a/plugin/search_course/lib/search_course_widget.class.php
+++ b/plugin/search_course/lib/search_course_widget.class.php
@@ -11,8 +11,8 @@
  */
 class SearchCourseWidget
 {
-    const PARAM_ACTION = 'action';
-    const ACTION_SUBSCRIBE = 'subscribe';
+    public const PARAM_ACTION = 'action';
+    public const ACTION_SUBSCRIBE = 'subscribe';
 
     /**
      * Returns $_POST data for $key is it exists or $default otherwise.
diff --git a/plugin/sepe/src/sepe_plugin.class.php b/plugin/sepe/src/sepe_plugin.class.php
index d019cd1cb0..9ac742c5d2 100644
--- a/plugin/sepe/src/sepe_plugin.class.php
+++ b/plugin/sepe/src/sepe_plugin.class.php
@@ -11,22 +11,22 @@
  */
 class SepePlugin extends Plugin
 {
-    const TABLE_SEPE_CENTER = 'plugin_sepe_center';
-    const TABLE_SEPE_ACTIONS = 'plugin_sepe_actions';
-    const TABLE_SEPE_SPECIALTY = 'plugin_sepe_specialty';
-    const TABLE_SEPE_SPECIALTY_CLASSROOM = 'plugin_sepe_specialty_classroom';
-    const TABLE_SEPE_CENTERS = 'plugin_sepe_centers';
-    const TABLE_SEPE_TUTORS = 'plugin_sepe_tutors';
-    const TABLE_SEPE_SPECIALTY_TUTORS = 'plugin_sepe_specialty_tutors';
-    const TABLE_SEPE_PARTICIPANTS = 'plugin_sepe_participants';
-    const TABLE_SEPE_PARTICIPANTS_SPECIALTY = 'plugin_sepe_participants_specialty';
-    const TABLE_SEPE_PARTICIPANTS_SPECIALTY_TUTORIALS = 'plugin_sepe_participants_specialty_tutorials';
-    const TABLE_SEPE_COURSE_ACTIONS = 'plugin_sepe_course_actions';
-    const TABLE_SEPE_TUTORS_COMPANY = 'plugin_sepe_tutors_company';
-    const TABLE_SEPE_TEACHING_COMPETENCE = 'plugin_sepe_teaching_competence';
-    const TABLE_SEPE_LOG_PARTICIPANT = 'plugin_sepe_log_participant';
-    const TABLE_SEPE_LOG_MOD_PARTICIPANT = 'plugin_sepe_log_mod_participant';
-    const TABLE_SEPE_LOG = 'plugin_sepe_log';
+    public const TABLE_SEPE_CENTER = 'plugin_sepe_center';
+    public const TABLE_SEPE_ACTIONS = 'plugin_sepe_actions';
+    public const TABLE_SEPE_SPECIALTY = 'plugin_sepe_specialty';
+    public const TABLE_SEPE_SPECIALTY_CLASSROOM = 'plugin_sepe_specialty_classroom';
+    public const TABLE_SEPE_CENTERS = 'plugin_sepe_centers';
+    public const TABLE_SEPE_TUTORS = 'plugin_sepe_tutors';
+    public const TABLE_SEPE_SPECIALTY_TUTORS = 'plugin_sepe_specialty_tutors';
+    public const TABLE_SEPE_PARTICIPANTS = 'plugin_sepe_participants';
+    public const TABLE_SEPE_PARTICIPANTS_SPECIALTY = 'plugin_sepe_participants_specialty';
+    public const TABLE_SEPE_PARTICIPANTS_SPECIALTY_TUTORIALS = 'plugin_sepe_participants_specialty_tutorials';
+    public const TABLE_SEPE_COURSE_ACTIONS = 'plugin_sepe_course_actions';
+    public const TABLE_SEPE_TUTORS_COMPANY = 'plugin_sepe_tutors_company';
+    public const TABLE_SEPE_TEACHING_COMPETENCE = 'plugin_sepe_teaching_competence';
+    public const TABLE_SEPE_LOG_PARTICIPANT = 'plugin_sepe_log_participant';
+    public const TABLE_SEPE_LOG_MOD_PARTICIPANT = 'plugin_sepe_log_mod_participant';
+    public const TABLE_SEPE_LOG = 'plugin_sepe_log';
 
     public $isAdminPlugin = true;
 
diff --git a/plugin/userremoteservice/src/user_remote_service_plugin.class.php b/plugin/userremoteservice/src/user_remote_service_plugin.class.php
index f968f0da39..927e25c0c6 100644
--- a/plugin/userremoteservice/src/user_remote_service_plugin.class.php
+++ b/plugin/userremoteservice/src/user_remote_service_plugin.class.php
@@ -6,7 +6,7 @@ use Doctrine\ORM\OptimisticLockException;
 
 class UserRemoteServicePlugin extends Plugin
 {
-    const TABLE = 'plugin_user_remote_service';
+    public const TABLE = 'plugin_user_remote_service';
 
     /**
      * UserRemoteServicePlugin constructor.
diff --git a/plugin/whispeakauth/Entity/LogEvent.php b/plugin/whispeakauth/Entity/LogEvent.php
index dbda0e5c58..bec31ede22 100644
--- a/plugin/whispeakauth/Entity/LogEvent.php
+++ b/plugin/whispeakauth/Entity/LogEvent.php
@@ -24,8 +24,8 @@ use Doctrine\ORM\Mapping as ORM;
  */
 class LogEvent
 {
-    const STATUS_FAILED = 0;
-    const STATUS_SUCCESS = 1;
+    public const STATUS_FAILED = 0;
+    public const STATUS_SUCCESS = 1;
 
     /**
      * @var int
diff --git a/plugin/whispeakauth/WhispeakAuthPlugin.php b/plugin/whispeakauth/WhispeakAuthPlugin.php
index 3b8517d751..5a7c3509aa 100644
--- a/plugin/whispeakauth/WhispeakAuthPlugin.php
+++ b/plugin/whispeakauth/WhispeakAuthPlugin.php
@@ -14,22 +14,22 @@ use Doctrine\ORM\Tools\SchemaTool;
  */
 class WhispeakAuthPlugin extends Plugin implements HookPluginInterface
 {
-    const SETTING_ENABLE = 'enable';
-    const SETTING_MAX_ATTEMPTS = 'max_attempts';
-    const SETTING_2FA = '2fa';
-    const SETTING_API_URL = 'api_url';
-    const SETTING_TOKEN = 'token';
-
-    const EXTRAFIELD_AUTH_UID = 'whispeak_auth_uid';
-    const EXTRAFIELD_LP_ITEM = 'whispeak_lp_item';
-    const EXTRAFIELD_QUIZ_QUESTION = 'whispeak_quiz_question';
-
-    const SESSION_FAILED_LOGINS = 'whispeak_failed_logins';
-    const SESSION_2FA_USER = 'whispeak_user_id';
-    const SESSION_LP_ITEM = 'whispeak_lp_item';
-    const SESSION_QUIZ_QUESTION = 'whispeak_quiz_question';
-    const SESSION_AUTH_PASSWORD = 'whispeak_auth_password';
-    const SESSION_SENTENCE_TEXT = 'whispeak_sentence_text';
+    public const SETTING_ENABLE = 'enable';
+    public const SETTING_MAX_ATTEMPTS = 'max_attempts';
+    public const SETTING_2FA = '2fa';
+    public const SETTING_API_URL = 'api_url';
+    public const SETTING_TOKEN = 'token';
+
+    public const EXTRAFIELD_AUTH_UID = 'whispeak_auth_uid';
+    public const EXTRAFIELD_LP_ITEM = 'whispeak_lp_item';
+    public const EXTRAFIELD_QUIZ_QUESTION = 'whispeak_quiz_question';
+
+    public const SESSION_FAILED_LOGINS = 'whispeak_failed_logins';
+    public const SESSION_2FA_USER = 'whispeak_user_id';
+    public const SESSION_LP_ITEM = 'whispeak_lp_item';
+    public const SESSION_QUIZ_QUESTION = 'whispeak_quiz_question';
+    public const SESSION_AUTH_PASSWORD = 'whispeak_auth_password';
+    public const SESSION_SENTENCE_TEXT = 'whispeak_sentence_text';
 
     /**
      * StudentFollowUpPlugin constructor.
diff --git a/plugin/xapi/src/XApiPlugin.php b/plugin/xapi/src/XApiPlugin.php
index b23449883f..86670d6e20 100644
--- a/plugin/xapi/src/XApiPlugin.php
+++ b/plugin/xapi/src/XApiPlugin.php
@@ -27,18 +27,18 @@ use Xabbuh\XApi\Serializer\Symfony\Serializer;
  */
 class XApiPlugin extends Plugin implements HookPluginInterface
 {
-    const SETTING_LRS_URL = 'lrs_url';
-    const SETTING_LRS_AUTH_USERNAME = 'lrs_auth_username';
-    const SETTING_LRS_AUTH_PASSWORD = 'lrs_auth_password';
-    const SETTING_UUID_NAMESPACE = 'uuid_namespace';
-    const SETTING_LRS_LP_ITEM_ACTIVE = 'lrs_lp_item_viewed_active';
-    const SETTING_LRS_LP_ACTIVE = 'lrs_lp_end_active';
-    const SETTING_LRS_QUIZ_ACTIVE = 'lrs_quiz_active';
-    const SETTING_LRS_QUIZ_QUESTION_ACTIVE = 'lrs_quiz_question_active';
-    const SETTING_LRS_PORTFOLIO_ACTIVE = 'lrs_portfolio_active';
-
-    const STATE_FIRST_LAUNCH = 'first_launch';
-    const STATE_LAST_LAUNCH = 'last_launch';
+    public const SETTING_LRS_URL = 'lrs_url';
+    public const SETTING_LRS_AUTH_USERNAME = 'lrs_auth_username';
+    public const SETTING_LRS_AUTH_PASSWORD = 'lrs_auth_password';
+    public const SETTING_UUID_NAMESPACE = 'uuid_namespace';
+    public const SETTING_LRS_LP_ITEM_ACTIVE = 'lrs_lp_item_viewed_active';
+    public const SETTING_LRS_LP_ACTIVE = 'lrs_lp_end_active';
+    public const SETTING_LRS_QUIZ_ACTIVE = 'lrs_quiz_active';
+    public const SETTING_LRS_QUIZ_QUESTION_ACTIVE = 'lrs_quiz_question_active';
+    public const SETTING_LRS_PORTFOLIO_ACTIVE = 'lrs_portfolio_active';
+
+    public const STATE_FIRST_LAUNCH = 'first_launch';
+    public const STATE_LAST_LAUNCH = 'last_launch';
 
     /**
      * XApiPlugin constructor.
diff --git a/plugin/zoom/lib/API/Meeting.php b/plugin/zoom/lib/API/Meeting.php
index b7b290ad68..6b9ec94ba8 100644
--- a/plugin/zoom/lib/API/Meeting.php
+++ b/plugin/zoom/lib/API/Meeting.php
@@ -16,10 +16,10 @@ class Meeting
     use BaseMeetingTrait;
     use JsonDeserializableTrait;
 
-    const TYPE_INSTANT = 1;
-    const TYPE_SCHEDULED = 2;
-    const TYPE_RECURRING_WITH_NO_FIXED_TIME = 3;
-    const TYPE_RECURRING_WITH_FIXED_TIME = 8;
+    public const TYPE_INSTANT = 1;
+    public const TYPE_SCHEDULED = 2;
+    public const TYPE_RECURRING_WITH_NO_FIXED_TIME = 3;
+    public const TYPE_RECURRING_WITH_FIXED_TIME = 8;
 
     /** @var string password to join. [a-z A-Z 0-9 @ - _ *]. Max of 10 characters. */
     public $password;
diff --git a/plugin/zoom/lib/API/MeetingList.php b/plugin/zoom/lib/API/MeetingList.php
index 77579665d1..cc21004b5e 100644
--- a/plugin/zoom/lib/API/MeetingList.php
+++ b/plugin/zoom/lib/API/MeetingList.php
@@ -15,10 +15,10 @@ class MeetingList
 {
     use Pagination;
 
-    const TYPE_SCHEDULED = 'scheduled'; // all valid past meetings (unexpired),
+    public const TYPE_SCHEDULED = 'scheduled'; // all valid past meetings (unexpired),
     // live meetings and upcoming scheduled meetings.
-    const TYPE_LIVE = 'live';           // all the ongoing meetings.
-    const TYPE_UPCOMING = 'upcoming';   // all upcoming meetings, including live meetings.
+    public const TYPE_LIVE = 'live';           // all the ongoing meetings.
+    public const TYPE_UPCOMING = 'upcoming';   // all upcoming meetings, including live meetings.
 
     /** @var MeetingListItem[] */
     public $meetings;
diff --git a/plugin/zoom/lib/API/MeetingSettings.php b/plugin/zoom/lib/API/MeetingSettings.php
index a82d6edfdd..353b8af942 100644
--- a/plugin/zoom/lib/API/MeetingSettings.php
+++ b/plugin/zoom/lib/API/MeetingSettings.php
@@ -13,13 +13,13 @@ class MeetingSettings
 {
     use JsonDeserializableTrait;
 
-    const APPROVAL_TYPE_AUTOMATICALLY_APPROVE = 0;
-    const APPROVAL_TYPE_MANUALLY_APPROVE = 1;
-    const APPROVAL_TYPE_NO_REGISTRATION_REQUIRED = 2;
+    public const APPROVAL_TYPE_AUTOMATICALLY_APPROVE = 0;
+    public const APPROVAL_TYPE_MANUALLY_APPROVE = 1;
+    public const APPROVAL_TYPE_NO_REGISTRATION_REQUIRED = 2;
 
-    const REGISTRATION_TYPE_REGISTER_ONCE_ATTEND_ANY = 1;
-    const REGISTRATION_TYPE_REGISTER_EACH = 2;
-    const REGISTRATION_TYPE_REGISTER_ONCE_CHOOSE = 3;
+    public const REGISTRATION_TYPE_REGISTER_ONCE_ATTEND_ANY = 1;
+    public const REGISTRATION_TYPE_REGISTER_EACH = 2;
+    public const REGISTRATION_TYPE_REGISTER_ONCE_CHOOSE = 3;
 
     /** @var bool Start video when the host joins the meeting */
     public $host_video;
diff --git a/plugin/zoom/lib/API/WebinarSchema.php b/plugin/zoom/lib/API/WebinarSchema.php
index 7e9f6ee1ae..5c2d535bae 100644
--- a/plugin/zoom/lib/API/WebinarSchema.php
+++ b/plugin/zoom/lib/API/WebinarSchema.php
@@ -12,9 +12,9 @@ class WebinarSchema
     use BaseMeetingTrait;
     use JsonDeserializableTrait;
 
-    const TYPE_WEBINAR = 5;
-    const TYPE_RECURRING_NO_FIXED_TIME = 6;
-    const TYPE_RECURRING_FIXED_TIME = 9;
+    public const TYPE_WEBINAR = 5;
+    public const TYPE_RECURRING_NO_FIXED_TIME = 6;
+    public const TYPE_RECURRING_FIXED_TIME = 9;
 
     public $uuid;
     public $id;
diff --git a/plugin/zoom/lib/API/WebinarSettings.php b/plugin/zoom/lib/API/WebinarSettings.php
index 405fc91f2c..b46671a782 100644
--- a/plugin/zoom/lib/API/WebinarSettings.php
+++ b/plugin/zoom/lib/API/WebinarSettings.php
@@ -10,13 +10,13 @@ class WebinarSettings
 {
     use JsonDeserializableTrait;
 
-    const APPROVAL_TYPE_AUTOMATICALLY_APPROVE = 0;
-    const APPROVAL_TYPE_MANUALLY_APPROVE = 1;
-    const APPROVAL_TYPE_NO_REGISTRATION_REQUIRED = 2;
+    public const APPROVAL_TYPE_AUTOMATICALLY_APPROVE = 0;
+    public const APPROVAL_TYPE_MANUALLY_APPROVE = 1;
+    public const APPROVAL_TYPE_NO_REGISTRATION_REQUIRED = 2;
 
-    const REGISTRATION_TYPE_REGISTER_ONCE_ATTEND_ANY = 1;
-    const REGISTRATION_TYPE_REGISTER_EACH = 2;
-    const REGISTRATION_TYPE_REGISTER_ONCE_CHOOSE = 3;
+    public const REGISTRATION_TYPE_REGISTER_ONCE_ATTEND_ANY = 1;
+    public const REGISTRATION_TYPE_REGISTER_EACH = 2;
+    public const REGISTRATION_TYPE_REGISTER_ONCE_CHOOSE = 3;
 
     /**
      * @var bool
diff --git a/plugin/zoom/lib/ZoomPlugin.php b/plugin/zoom/lib/ZoomPlugin.php
index 842d3d7277..1ee6b2cc70 100644
--- a/plugin/zoom/lib/ZoomPlugin.php
+++ b/plugin/zoom/lib/ZoomPlugin.php
@@ -35,9 +35,9 @@ use Doctrine\ORM\Tools\ToolsException;
  */
 class ZoomPlugin extends Plugin
 {
-    const RECORDING_TYPE_CLOUD = 'cloud';
-    const RECORDING_TYPE_LOCAL = 'local';
-    const RECORDING_TYPE_NONE = 'none';
+    public const RECORDING_TYPE_CLOUD = 'cloud';
+    public const RECORDING_TYPE_LOCAL = 'local';
+    public const RECORDING_TYPE_NONE = 'none';
     public $isCoursePlugin = true;
 
     /**
diff --git a/src/Chamilo/CoreBundle/Entity/Course.php b/src/Chamilo/CoreBundle/Entity/Course.php
index 154e3c6ce9..c36c2caccd 100644
--- a/src/Chamilo/CoreBundle/Entity/Course.php
+++ b/src/Chamilo/CoreBundle/Entity/Course.php
@@ -31,11 +31,11 @@ use Symfony\Component\Validator\Constraints as Assert;
  */
 class Course
 {
-    const CLOSED = 0;
-    const REGISTERED = 1;
-    const OPEN_PLATFORM = 2;
-    const OPEN_WORLD = 3;
-    const HIDDEN = 4;
+    public const CLOSED = 0;
+    public const REGISTERED = 1;
+    public const OPEN_PLATFORM = 2;
+    public const OPEN_WORLD = 3;
+    public const HIDDEN = 4;
 
     /**
      * @var int
diff --git a/src/Chamilo/CoreBundle/Entity/SequenceResource.php b/src/Chamilo/CoreBundle/Entity/SequenceResource.php
index 9697c96423..01e603715c 100644
--- a/src/Chamilo/CoreBundle/Entity/SequenceResource.php
+++ b/src/Chamilo/CoreBundle/Entity/SequenceResource.php
@@ -13,8 +13,8 @@ use Doctrine\ORM\Mapping as ORM;
  */
 class SequenceResource
 {
-    const COURSE_TYPE = 1;
-    const SESSION_TYPE = 2;
+    public const COURSE_TYPE = 1;
+    public const SESSION_TYPE = 2;
 
     /**
      * @var int
diff --git a/src/Chamilo/CoreBundle/Entity/Session.php b/src/Chamilo/CoreBundle/Entity/Session.php
index a3d10dc780..751044672f 100644
--- a/src/Chamilo/CoreBundle/Entity/Session.php
+++ b/src/Chamilo/CoreBundle/Entity/Session.php
@@ -28,14 +28,14 @@ use Doctrine\ORM\Mapping as ORM;
  */
 class Session
 {
-    const VISIBLE = 1;
-    const READ_ONLY = 2;
-    const INVISIBLE = 3;
-    const AVAILABLE = 4;
-
-    const STUDENT = 0;
-    const DRH = 1;
-    const COACH = 2;
+    public const VISIBLE = 1;
+    public const READ_ONLY = 2;
+    public const INVISIBLE = 3;
+    public const AVAILABLE = 4;
+
+    public const STUDENT = 0;
+    public const DRH = 1;
+    public const COACH = 2;
 
     /**
      * @var int
diff --git a/src/Chamilo/CoreBundle/Entity/SessionRelCourseRelUser.php b/src/Chamilo/CoreBundle/Entity/SessionRelCourseRelUser.php
index f7fc0aa088..b23ce0b666 100644
--- a/src/Chamilo/CoreBundle/Entity/SessionRelCourseRelUser.php
+++ b/src/Chamilo/CoreBundle/Entity/SessionRelCourseRelUser.php
@@ -20,8 +20,8 @@ use Doctrine\ORM\Mapping as ORM;
  */
 class SessionRelCourseRelUser
 {
-    const STATUS_STUDENT = 0;
-    const STATUS_COURSE_COACH = 2;
+    public const STATUS_STUDENT = 0;
+    public const STATUS_COURSE_COACH = 2;
 
     public $statusList = [
         0 => 'student',
diff --git a/src/Chamilo/CoreBundle/Entity/Skill.php b/src/Chamilo/CoreBundle/Entity/Skill.php
index 6d953216cc..51c22b0579 100644
--- a/src/Chamilo/CoreBundle/Entity/Skill.php
+++ b/src/Chamilo/CoreBundle/Entity/Skill.php
@@ -19,8 +19,8 @@ use Doctrine\ORM\Mapping as ORM;
  */
 class Skill
 {
-    const STATUS_DISABLED = 0;
-    const STATUS_ENABLED = 1;
+    public const STATUS_DISABLED = 0;
+    public const STATUS_ENABLED = 1;
 
     /**
      * @ORM\ManyToOne(targetEntity="Chamilo\SkillBundle\Entity\Profile", inversedBy="skills")
diff --git a/src/Chamilo/CourseBundle/Component/CourseCopy/CourseBuilder.php b/src/Chamilo/CourseBundle/Component/CourseCopy/CourseBuilder.php
index 3281b48100..31b5bc2edf 100644
--- a/src/Chamilo/CourseBundle/Component/CourseCopy/CourseBuilder.php
+++ b/src/Chamilo/CourseBundle/Component/CourseCopy/CourseBuilder.php
@@ -2124,7 +2124,7 @@ class CourseBuilder
     ) {
         $courseInfo = api_get_course_info_by_id($courseId);
         $courseCode = $courseInfo['code'];
-        $cats = Category:: load(
+        $cats = Category::load(
             null,
             null,
             $courseCode,
diff --git a/src/Chamilo/CourseBundle/Component/CourseCopy/CourseRestorer.php b/src/Chamilo/CourseBundle/Component/CourseCopy/CourseRestorer.php
index db69843b4e..46af752b2b 100644
--- a/src/Chamilo/CourseBundle/Component/CourseCopy/CourseRestorer.php
+++ b/src/Chamilo/CourseBundle/Component/CourseCopy/CourseRestorer.php
@@ -3187,7 +3187,7 @@ class CourseRestorer
                         if (!is_dir($dest.'/'.$file)) {
                             mkdir($dest.'/'.$file);
                         }
-                        self:: allow_create_all_directory($path, $dest.'/'.$file, $overwrite);
+                        self::allow_create_all_directory($path, $dest.'/'.$file, $overwrite);
                     }
                 }
             }
@@ -3703,7 +3703,7 @@ class CourseRestorer
             $resources = $this->course->resources;
             $destinationCourseCode = $this->destination_course_info['code'];
             // Delete destination gradebook
-            $cats = \Category:: load(
+            $cats = \Category::load(
                 null,
                 null,
                 $destinationCourseCode,
diff --git a/src/Chamilo/CourseBundle/Entity/CCourseDescription.php b/src/Chamilo/CourseBundle/Entity/CCourseDescription.php
index c140e675d1..299830c8d7 100644
--- a/src/Chamilo/CourseBundle/Entity/CCourseDescription.php
+++ b/src/Chamilo/CourseBundle/Entity/CCourseDescription.php
@@ -13,14 +13,14 @@ use Doctrine\ORM\Mapping as ORM;
  */
 class CCourseDescription
 {
-    const TYPE_DESCRIPTION = 1;
-    const TYPE_OBJECTIVES = 2;
-    const TYPE_TOPICS = 3;
-    const TYPE_METHODOLOGY = 4;
-    const TYPE_COURSE_MATERIAL = 5;
-    const TYPE_RESOURCES = 6;
-    const TYPE_ASSESSMENT = 7;
-    const TYPE_CUSTOM = 8;
+    public const TYPE_DESCRIPTION = 1;
+    public const TYPE_OBJECTIVES = 2;
+    public const TYPE_TOPICS = 3;
+    public const TYPE_METHODOLOGY = 4;
+    public const TYPE_COURSE_MATERIAL = 5;
+    public const TYPE_RESOURCES = 6;
+    public const TYPE_ASSESSMENT = 7;
+    public const TYPE_CUSTOM = 8;
 
     /**
      * @var int
diff --git a/src/Chamilo/CourseBundle/Entity/CForumPost.php b/src/Chamilo/CourseBundle/Entity/CForumPost.php
index 9ea96a73dc..6a71cc9470 100644
--- a/src/Chamilo/CourseBundle/Entity/CForumPost.php
+++ b/src/Chamilo/CourseBundle/Entity/CForumPost.php
@@ -22,9 +22,9 @@ use Doctrine\ORM\Mapping as ORM;
  */
 class CForumPost
 {
-    const STATUS_VALIDATED = 1;
-    const STATUS_WAITING_MODERATION = 2;
-    const STATUS_REJECTED = 3;
+    public const STATUS_VALIDATED = 1;
+    public const STATUS_WAITING_MODERATION = 2;
+    public const STATUS_REJECTED = 3;
 
     /**
      * @var int
diff --git a/src/Chamilo/CourseBundle/Entity/CStudentPublication.php b/src/Chamilo/CourseBundle/Entity/CStudentPublication.php
index 151d781f84..d48d09afb1 100644
--- a/src/Chamilo/CourseBundle/Entity/CStudentPublication.php
+++ b/src/Chamilo/CourseBundle/Entity/CStudentPublication.php
@@ -22,7 +22,7 @@ use Doctrine\ORM\Mapping as ORM;
 class CStudentPublication
 {
     /** @var int 255 chars from url column - 5 chars from 'work/' - 32 chars from filename hash - 1 char */
-    const WORK_TITLE_MAX_LENGTH = 217;
+    public const WORK_TITLE_MAX_LENGTH = 217;
 
     /**
      * @var int
diff --git a/src/Chamilo/PageBundle/Entity/User.php b/src/Chamilo/PageBundle/Entity/User.php
index 8f4bf5037f..7d707057bb 100644
--- a/src/Chamilo/PageBundle/Entity/User.php
+++ b/src/Chamilo/PageBundle/Entity/User.php
@@ -20,12 +20,12 @@ use Symfony\Component\Validator\Mapping\ClassMetadata;
 
 class User extends BaseUser
 {
-    const COURSE_MANAGER = 1;
-    const TEACHER = 1;
-    const SESSION_ADMIN = 3;
-    const DRH = 4;
-    const STUDENT = 5;
-    const ANONYMOUS = 6;
+    public const COURSE_MANAGER = 1;
+    public const TEACHER = 1;
+    public const SESSION_ADMIN = 3;
+    public const DRH = 4;
+    public const STUDENT = 5;
+    public const ANONYMOUS = 6;
 
     /**
      * @var int
diff --git a/src/Chamilo/ThemeBundle/Event/ThemeEvents.php b/src/Chamilo/ThemeBundle/Event/ThemeEvents.php
index 11acd16122..b9d158c323 100644
--- a/src/Chamilo/ThemeBundle/Event/ThemeEvents.php
+++ b/src/Chamilo/ThemeBundle/Event/ThemeEvents.php
@@ -11,39 +11,39 @@ class ThemeEvents
     /**
      * Used to receive notification data.
      */
-    const THEME_NOTIFICATIONS = 'theme.notifications';
+    public const THEME_NOTIFICATIONS = 'theme.notifications';
     /**
      * Used to receive message data.
      */
-    const THEME_MESSAGES = 'theme.messages';
+    public const THEME_MESSAGES = 'theme.messages';
     /**
      * Used to receive task data.
      */
-    const THEME_TASKS = 'theme.tasks';
+    public const THEME_TASKS = 'theme.tasks';
 
-    const THEME_NAVBAR_USER = 'theme.navbar_user';
+    public const THEME_NAVBAR_USER = 'theme.navbar_user';
     /**
      * used to receive breadcrumb data.
      */
-    const THEME_BREADCRUMB = 'theme.breadcrumb';
+    public const THEME_BREADCRUMB = 'theme.breadcrumb';
     /**
      * used to receive the current user for the sidebar.
      */
-    const THEME_SIDEBAR_USER = 'theme.sidebar_user';
+    public const THEME_SIDEBAR_USER = 'theme.sidebar_user';
     /**
      * Used for searching.
      *
      * @unused
      */
-    const THEME_SIDEBAR_SEARCH = 'theme.sidebar_search';
+    public const THEME_SIDEBAR_SEARCH = 'theme.sidebar_search';
     /**
      * Used to receive the sidebar menu data.
      */
-    const THEME_SIDEBAR_SETUP_MENU = 'theme.sidebar_setup_menu';
+    public const THEME_SIDEBAR_SETUP_MENU = 'theme.sidebar_setup_menu';
     /**
      * Used to receive the sidebar menu data.
      */
-    const THEME_SIDEBAR_SETUP_MENU_KNP = 'theme.sidebar_setup_menu_knp';
+    public const THEME_SIDEBAR_SETUP_MENU_KNP = 'theme.sidebar_setup_menu_knp';
 
-    const THEME_SIDEBAR_ACTIVATE_MENU = 'theme.sidebar_activate_menu';
+    public const THEME_SIDEBAR_ACTIVATE_MENU = 'theme.sidebar_activate_menu';
 }
diff --git a/src/Chamilo/ThemeBundle/Model/TaskModel.php b/src/Chamilo/ThemeBundle/Model/TaskModel.php
index f090d22286..8addcbf28b 100644
--- a/src/Chamilo/ThemeBundle/Model/TaskModel.php
+++ b/src/Chamilo/ThemeBundle/Model/TaskModel.php
@@ -10,13 +10,13 @@ namespace Chamilo\ThemeBundle\Model;
  */
 class TaskModel implements TaskInterface
 {
-    const COLOR_AQUA = 'aqua';
+    public const COLOR_AQUA = 'aqua';
 
-    const COLOR_GREEN = 'green';
+    public const COLOR_GREEN = 'green';
 
-    const COLOR_RED = 'red';
+    public const COLOR_RED = 'red';
 
-    const COLOR_YELLOW = 'yellow';
+    public const COLOR_YELLOW = 'yellow';
 
     /**
      * @var int
diff --git a/src/Chamilo/UserBundle/Entity/User.php b/src/Chamilo/UserBundle/Entity/User.php
index 2c1521252b..f040d84faa 100644
--- a/src/Chamilo/UserBundle/Entity/User.php
+++ b/src/Chamilo/UserBundle/Entity/User.php
@@ -33,12 +33,12 @@ use Symfony\Component\Validator\Mapping\ClassMetadata;
  */
 class User implements UserInterface //implements ParticipantInterface, ThemeUser
 {
-    const COURSE_MANAGER = 1;
-    const TEACHER = 1;
-    const SESSION_ADMIN = 3;
-    const DRH = 4;
-    const STUDENT = 5;
-    const ANONYMOUS = 6;
+    public const COURSE_MANAGER = 1;
+    public const TEACHER = 1;
+    public const SESSION_ADMIN = 3;
+    public const DRH = 4;
+    public const STUDENT = 5;
+    public const ANONYMOUS = 6;
 
     /**
      * @var int