diff --git a/src/patterns/01-core/ckeditor/ckeditor.js b/src/patterns/01-core/ckeditor/ckeditor.js
index 411a853f57ae2cef1146aae3356b72442c315598..f42b09aca585e4a330dc49602d8e261afc4240ad 100644
--- a/src/patterns/01-core/ckeditor/ckeditor.js
+++ b/src/patterns/01-core/ckeditor/ckeditor.js
@@ -2,13 +2,15 @@
  * Ckeditor Modal
  */
 (function ($, Drupal) {
-  if ($.ui.dialog) {
-    orig_allowInteraction = $.ui.dialog.prototype._allowInteraction;
-    $.ui.dialog.prototype._allowInteraction = function (event) {
-      if ($(event.target).closest('.cke_dialog').length) {
-        return true;
-      }
-      return orig_allowInteraction.apply(this, arguments);
-    };
+  if ($.ui !== undefined) {
+    if ($.ui.dialog) {
+      orig_allowInteraction = $.ui.dialog.prototype._allowInteraction;
+      $.ui.dialog.prototype._allowInteraction = function (event) {
+        if ($(event.target).closest('.cke_dialog').length) {
+          return true;
+        }
+        return orig_allowInteraction.apply(this, arguments);
+      };
+    }
   }
 })(jQuery, Drupal);