diff --git a/modules/backend/classes/Controller.php b/modules/backend/classes/Controller.php
index <HASH>..<HASH> 100644
--- a/modules/backend/classes/Controller.php
+++ b/modules/backend/classes/Controller.php
@@ -555,6 +555,13 @@ class Controller extends Extendable
             }
         }
 
+        /*
+         * Generic handler that does nothing
+         */
+        if ($handler == 'onAjax') {
+            return true;
+        }
+
         return false;
     }
 
diff --git a/modules/cms/classes/Controller.php b/modules/cms/classes/Controller.php
index <HASH>..<HASH> 100644
--- a/modules/cms/classes/Controller.php
+++ b/modules/cms/classes/Controller.php
@@ -723,6 +723,13 @@ class Controller
             }
         }
 
+        /*
+         * Generic handler that does nothing
+         */
+        if ($handler == 'onAjax') {
+            return true;
+        }
+
         return false;
     }
Add generic onAjax handler that does nothing