diff --git a/core/modules/menu_ui/menu_ui.js b/core/modules/menu_ui/menu_ui.js
index 2103952..130b54e 100644
--- a/core/modules/menu_ui/menu_ui.js
+++ b/core/modules/menu_ui/menu_ui.js
@@ -8,8 +8,12 @@
   "use strict";
 
   /**
+   * Set a summary on the menu link form.
    *
    * @type {Drupal~behavior}
+   *
+   * @prop {Drupal~behaviorAttach} attach
+   *   Find the form and call `drupalSetSummary` on it.
    */
   Drupal.behaviors.menuUiDetailsSummaries = {
     attach: function (context) {
@@ -29,14 +33,17 @@
    * Automatically fill in a menu link title, if possible.
    *
    * @type {Drupal~behavior}
+   *   Attaches change and keyup behavior for automatically filling out menu
+   *   link titles.
    */
   Drupal.behaviors.menuUiLinkAutomaticTitle = {
     attach: function (context) {
       var $context = $(context);
       $context.find('.menu-link-form').each(function () {
         var $this = $(this);
-        // Try to find menu settings widget elements as well as a 'title' field in
-        // the form, but play nicely with user permissions and form alterations.
+        // Try to find menu settings widget elements as well as a 'title' field
+        // in the form, but play nicely with user permissions and form
+        // alterations.
         var $checkbox = $this.find('.form-item-menu-enabled input');
         var $link_title = $context.find('.form-item-menu-title input');
         var $title = $this.closest('form').find('.form-item-title-0-value input');
@@ -44,8 +51,9 @@
         if (!($checkbox.length && $link_title.length && $title.length)) {
           return;
         }
-        // If there is a link title already, mark it as overridden. The user expects
-        // that toggling the checkbox twice will take over the node's title.
+        // If there is a link title already, mark it as overridden. The user
+        // expects that toggling the checkbox twice will take over the node's
+        // title.
         if ($checkbox.is(':checked') && $link_title.val().length) {
           $link_title.data('menuLinkAutomaticTitleOverridden', true);
         }