diff --git a/main/admin/configure_extensions.php b/main/admin/configure_extensions.php
index d7d6186db2..ad04b9ddfb 100755
--- a/main/admin/configure_extensions.php
+++ b/main/admin/configure_extensions.php
@@ -68,6 +68,7 @@ if (isset($_POST['activeExtension'])) {
             Database::query($sql);
             break;
     }
+    api_flush_settings_cache(api_get_current_access_url_id());
 }
 
 $listActiveServices = [];
diff --git a/main/admin/configure_plugin.php b/main/admin/configure_plugin.php
index 82681c286c..b22e722a88 100755
--- a/main/admin/configure_plugin.php
+++ b/main/admin/configure_plugin.php
@@ -77,7 +77,7 @@ if (isset($form)) {
                 '',
                 '',
                 '',
-                api_get_current_access_url_id(),
+                $accessUrlId,
                 1
             );
         }
@@ -88,6 +88,7 @@ if (isset($form)) {
             $pluginName,
             api_get_utc_datetime()
         );
+        api_flush_settings_cache($accessUrlId);
 
         if (!empty($pluginInfo['plugin_class'])) {
             /** @var \Plugin $objPlugin */
diff --git a/main/admin/settings.php b/main/admin/settings.php
index 88c44c7e63..950ba46ec0 100755
--- a/main/admin/settings.php
+++ b/main/admin/settings.php
@@ -96,7 +96,11 @@ $url_id = api_get_current_access_url_id();
 
 $settings = null;
 $flushSettings = false;
-$cacheAvailable = api_get_configuration_value('apc');
+$multipleUrlsEnabled = false;
+
+if (api_is_multiple_url_enabled()) {
+    $multipleUrlsEnabled = true;
+}
 
 // Build the form.
 if (!empty($_GET['category']) &&
@@ -107,7 +111,6 @@ if (!empty($_GET['category']) &&
     $settings = $settings_array['settings'];
     $settings_by_access_list = $settings_array['settings_by_access_list'];
     $form = generateSettingsForm($settings, $settings_by_access_list);
-    $multipleUrlsEnabled = false;
 
     if ($form->validate()) {
         $values = $form->exportValues();
@@ -115,8 +118,7 @@ if (!empty($_GET['category']) &&
         $mark_all = false;
         $un_mark_all = false;
 
-        if (api_is_multiple_url_enabled()) {
-            $multipleUrlsEnabled = true;
+        if ($multipleUrlsEnabled) {
             if (isset($values['buttons_in_action_right']) &&
                 isset($values['buttons_in_action_right']['mark_all'])
             ) {
@@ -306,24 +308,8 @@ if (!empty($_GET['category']) &&
             api_get_utc_datetime(),
             $user_id
         );
-        if ($cacheAvailable && $flushSettings) {
-            // Delete the APCu-stored settings array, if present
-            $apcRootVarName = api_get_configuration_value('apc_prefix').'settings_';
-            $apcVarName = $apcRootVarName.$url_id;
-            apcu_delete($apcVarName);
-            if ($multipleUrlsEnabled && $url_id === 1) {
-                // if we are on the main URL of a multi-url portal, we must
-                // invalidate the cache for all other URLs as well as some
-                // main settings span multiple URLs
-                $urls = api_get_access_urls();
-                foreach ($urls as $i => $row) {
-                    if ($row['id'] == 1) {
-                        continue;
-                    }
-                    $apcVarName = $apcRootVarName.$row['id'];
-                    apcu_delete($apcVarName);
-                }
-            }
+        if ($flushSettings) {
+            api_flush_settings_cache($url_id);
         }
         // Add event configuration settings variable to the system log.
         if (is_array($keys) && count($keys) > 0) {
@@ -458,6 +444,7 @@ if (!empty($_GET['category'])) {
     switch ($_GET['category']) {
         case 'Regions':
             handleRegions();
+            $flushSettings = true;
             break;
         case 'Plugins':
             // Displaying the extensions: Plugins.
@@ -510,16 +497,19 @@ if (!empty($_GET['category'])) {
             echo '</div>';
 
             echo '</div>';
+            $flushSettings = true;
             break;
         case 'Stylesheets':
             // Displaying the extensions: Stylesheets.
             handleStylesheets();
+            $flushSettings = true;
             break;
         case 'Search':
             handleSearch();
             break;
         case 'Templates':
             handleTemplates();
+            $flushSettings = true;
             break;
         case 'search_setting':
             if (isset($_REQUEST['search_field'])) {
@@ -534,6 +524,9 @@ if (!empty($_GET['category'])) {
     }
 }
 $content = ob_get_clean();
+if ($flushSettings) {
+    api_flush_settings_cache($url_id);
+}
 
 // Including the header (banner).
 Display::display_header($tool_name);
diff --git a/main/inc/lib/api.lib.php b/main/inc/lib/api.lib.php
index 27a10076d5..3b5f05411d 100755
--- a/main/inc/lib/api.lib.php
+++ b/main/inc/lib/api.lib.php
@@ -10390,3 +10390,34 @@ function api_calculate_increment_percent(int $newValue, int $oldValue)
 
     return $result;
 }
+
+/**
+ * Erase settings from cache (because of some update) if applicable
+ * @param   int $url_id The ID of the present URL
+ */
+function api_flush_settings_cache(int $url_id): bool
+{
+    $cacheAvailable = api_get_configuration_value('apc');
+    if (!$cacheAvailable) {
+        return false;
+    }
+    $apcRootVarName = api_get_configuration_value('apc_prefix').'settings_';
+    // Delete the APCu-stored settings array, if present
+    $apcVarName = $apcRootVarName.$url_id;
+    apcu_delete($apcVarName);
+    if (api_is_multiple_url_enabled() && $url_id === 1) {
+        // if we are on the main URL of a multi-url portal, we must
+        // invalidate the cache for all other URLs as well as some
+        // main settings span multiple URLs
+        $urls = api_get_access_urls();
+        foreach ($urls as $i => $row) {
+            if ($row['id'] == 1) {
+                continue;
+            }
+            $apcVarName = $apcRootVarName.$row['id'];
+            apcu_delete($apcVarName);
+        }
+    }
+
+    return true;
+}