add explanation how to keep the current filters. fixes #2808

Resources/doc/cookbook/recipe_custom_action.rst

@@ -120,6 +120,12 @@ to implement a ``clone`` action.
 Here we first get the id of the object, see if it exists then clone it and insert the clone
 as a new object. Finally we set a flash message indicating success and redirect to the list view.
 
+If you want to add the current filter parameters to the redirect url you can add them to the `generateUrl` method:
+
+.. code-block:: php
+
+    return new RedirectResponse($this->admin->generateUrl('list', array('filter' => $this->admin->getFilterParameters())));
+
 Using template in new controller
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