diff --git a/main/forum/forumfunction.inc.php b/main/forum/forumfunction.inc.php
index f7270b827e..275996ac39 100755
--- a/main/forum/forumfunction.inc.php
+++ b/main/forum/forumfunction.inc.php
@@ -5789,6 +5789,8 @@ function send_notifications($forum_id = 0, $thread_id = 0, $post_id = 0)
     }
 
     $current_thread = get_thread_information($forum_id, $thread_id);
+    $courseInfo = api_get_course_info_by_id($current_thread['c_id']);
+    $courseCode = $courseInfo['code'];
 
     // User who subscribed to the thread
     if ($thread_id != 0) {
@@ -5806,8 +5808,20 @@ function send_notifications($forum_id = 0, $thread_id = 0, $post_id = 0)
 
     if (is_array($users_to_be_notified)) {
         foreach ($users_to_be_notified as $value) {
-            $userInfo = api_get_user_info($value['user_id']);
-            send_mail($userInfo, $forumInfo, $current_thread, $postInfo);
+            $notifyUser = true;
+            if ((api_get_course_setting('share_forums_in_sessions',$courseCode) === -1 || !api_get_course_setting('share_forums_in_sessions',$courseCode)) && $current_thread['session_id'] != 0) {
+                $notifyUser = false;
+                $userSessions = SessionManager::get_sessions_by_user($value['user_id']);
+                foreach ($userSessions as $userSession) {
+                    if ($userSession['session_id'] == $current_thread['session_id']) {
+                        $notifyUser = true;
+                    }
+                }
+            }
+            if ($notifyUser === true) {
+                $userInfo = api_get_user_info($value['user_id']);
+                send_mail($userInfo, $forumInfo, $current_thread, $postInfo);
+            }
         }
     }
 }
diff --git a/main/inc/lib/sessionmanager.lib.php b/main/inc/lib/sessionmanager.lib.php
index 186d99d987..49a951d983 100755
--- a/main/inc/lib/sessionmanager.lib.php
+++ b/main/inc/lib/sessionmanager.lib.php
@@ -2337,6 +2337,8 @@ class SessionManager
                         }
                     }
                 }
+                $courseInfo = api_get_course_info_by_id($courseId);
+                $courseCode = $courseInfo['code'];
 
                 // Replace with this new function
                 // insert new users into session_rel_course_rel_user and ignore if they already exist
@@ -2357,6 +2359,25 @@ class SessionManager
                             if (Database::affected_rows($result)) {
                                 $nbr_users++;
                             }
+                            if (!empty($courseInfo)) {
+                                $enregUserInfo = api_get_user_info($enreg_user);
+                                $subscribe = (int) api_get_course_setting('subscribe_users_to_forum_notifications', $courseCode);
+                                if ($subscribe === 1) {
+                                    require_once api_get_path(SYS_CODE_PATH).'forum/forumfunction.inc.php';
+                                    $forums = get_forums(0, $courseCode, true, $sessionId);
+                                    foreach ($forums as $forum) {
+                                        $forumId = $forum['iid'];
+                                        set_notification('forum', $forumId, false, $enregUserInfo, $courseInfo);
+                                    }
+                                    if (api_get_configuration_value('subscribe_users_to_forum_notifications_also_in_base_course')) {
+                                        $forums = get_forums(0, $courseCode, true, 0);
+                                        foreach ($forums as $forum) {
+                                            $forumId = $forum['iid'];
+                                            set_notification('forum', $forumId, false, $enregUserInfo, $courseInfo);
+                                        }
+                                    }
+                                }
+                            }
 
                             Event::addEvent(
                                 LOG_SESSION_ADD_USER_COURSE,
@@ -2646,9 +2667,13 @@ class SessionManager
         $courseId = $courseInfo['real_id'];
         $subscribe = (int) api_get_course_setting('subscribe_users_to_forum_notifications', $course_code);
         $forums = [];
+        $forumsBaseCourse = [];
         if ($subscribe === 1) {
             require_once api_get_path(SYS_CODE_PATH).'forum/forumfunction.inc.php';
             $forums = get_forums(0, $course_code, true, $session_id);
+            if (api_get_configuration_value('subscribe_users_to_forum_notifications_also_in_base_course')) {
+                $forumsBaseCourse = get_forums(0, $courseCode, true, 0);
+            }
         }
 
         if ($removeUsersNotInList) {
@@ -2705,6 +2730,13 @@ class SessionManager
                     set_notification('forum', $forumId, false, $userInfo, $courseInfo);
                 }
             }
+            if (!empty($forumsBaseCourse)) {
+                $userInfo = api_get_user_info($enreg_user);
+                foreach ($forumsBaseCourse as $forum) {
+                    $forumId = $forum['iid'];
+                    set_notification('forum', $forumId, false, $userInfo, $courseInfo);
+                }
+            }
 
             // Checking if user exists in session - user table.
             $sql = "SELECT count(user_id) as count
diff --git a/main/install/configuration.dist.php b/main/install/configuration.dist.php
index 7a6a814acc..cd28351fed 100755
--- a/main/install/configuration.dist.php
+++ b/main/install/configuration.dist.php
@@ -1216,6 +1216,11 @@ $_configuration['required_extra_fields_in_profile'] = [
 // Requires new forum_category and forum_post "language" extra fields (multiple select)
 //$_configuration['allow_forum_post_revisions'] = false;
 
+//Allows to subscribe to notification of forums of the base course for users subscribed in a session
+//Only works if subscribe_users_to_forum_notifications is set to true in the course's settings
+//$_configuration['subscribe_users_to_forum_notifications_also_in_base_course'] = false;
+
+
 // Allow to show users in a map, users need to have a coordinates extra field BT#15176
 //$_configuration['allow_social_map_fields'] = ['fields' => ['terms_villedustage', 'terms_ville']];