Issue #3391546: Replace deprecated core/jquery.once for Drupal 10 support

js/private_message_form.js

@@ -3,7 +3,7 @@
  * Adds JS functionality to the Private Message form.
  */
 
-(function ($, Drupal, drupalSettings) {
+(function ($, Drupal, drupalSettings, once) {
 
   'use strict';
 
@@ -32,7 +32,7 @@
    * @param {Object} context The context.
    */
   function submitButtonListener(context) {
-    $(context).parent().find('.private-message-add-form textarea').once('private-message-form-submit-button-listener').each(function () {
+    $(once('private-message-form-submit-button-listener', '.private-message-add-form textarea', context)).each(function () {
       $(this).keyup(submitKeyPress);
     });
   }
@@ -47,4 +47,4 @@
     }
   };
 
-}(jQuery, Drupal, drupalSettings));
+}(jQuery, Drupal, drupalSettings, once));