Ensure plugins are dynamically loaded in CKEditor 5

With the new installation format of CKEditor, plugins are no longer
automatically unwrapped when the editor is instantiated. Instead, we
must explicitly load plugins or `extraPlugins` and provide a reference
to the loaded class.

This change ensures that all required plugins are properly registered
before initialization, preventing missing plugin errors and maintaining
expected functionality.

share/static/js/util.js

@@ -508,9 +508,33 @@ async function ReplaceAllTextareas(elt) {
 
             // Customize shouldNotGroupWhenFull based on textarea width
             const initArgs = JSON.parse(JSON.stringify(RT.Config.MessageBoxRichTextInitArguments));
-            initArgs.toolbar.shouldNotGroupWhenFull = textArea.offsetWidth >= 600 ? true : false;
+            initArgs.toolbar.shouldNotGroupWhenFull = initArgs.toolbar.shouldNotGroupWhenFull = textArea.offsetWidth >= 600 ? true : false;
+
+            // Load core plugins from CKEDITOR
+            const corePlugins = [];
+            for (const plugin of initArgs.plugins || []) {
+                if (CKEDITOR?.[plugin]) {
+                    corePlugins.push(CKEDITOR[plugin]);
+                } else {
+                    console.error(`Core CKEditor plugin "${plugin}" not found.`);
+                }
+            }
+
+            // Load extra (third-party) plugins from window
+            const thirdPartyPlugins = [];
+            for (const plugin of initArgs.extraPlugins || []) {
+                if (window[plugin]?.[plugin]) {
+                    thirdPartyPlugins.push(window[plugin][plugin]);
+                } else {
+                    console.error(`Third-party CKEditor plugin "${plugin}" not found.`);
+                }
+            }
+
+            // Combine core and third-party plugins
+            initArgs.plugins = [...corePlugins, ...thirdPartyPlugins];
+            initArgs.extraPlugins = []; // Clear extraPlugins as they're now included
 
-            ClassicEditor
+            CKEDITOR.ClassicEditor
                 .create( textArea, initArgs )
                 .then(editor => {
                     RT_CKEditor.instances[editor.sourceElement.name] = editor;