diff --git a/packages/pageflow/src/editor/views/EditorView.js b/packages/pageflow/src/editor/views/EditorView.js
index <HASH>..<HASH> 100644
--- a/packages/pageflow/src/editor/views/EditorView.js
+++ b/packages/pageflow/src/editor/views/EditorView.js
@@ -54,6 +54,7 @@ export const EditorView = Backbone.View.extend({
       resizerTip: I18n.t('pageflow.editor.views.editor_views.resize_editor'),
       enableCursorHotkey: false,
       fxName: 'none',
+      maskIframesOnResize: true,
 
       onresize: function() {
         app.trigger('resize');
@@ -74,4 +75,4 @@ export const EditorView = Backbone.View.extend({
       event.stopPropagation();
     }
   }
-});
\ No newline at end of file
+});
Ensure resizing editor sidebar works over iframes

The option prevents iframes from capturing mouse events, which can
cause the dragged resizer to get stuck. This used to be a problem
already with rich text editors, which are iframes. Now that the
preview uses an iframe the problem got worse.

REDMINE-<I>