Fix custom layout element not properly update

In view designer:

• edit a layout, save
• edit again without saving (visual editor and / or code editor)
• revert
• select layout, click customize => end up with customized layout (latest unsaved changes)
• click on the layout name again => end up with default layout

note
This might be due to "old" element still being on DOM and it takes a while to get default element and replace it ?