TYPO3 Core

Problem:
After resizing the preview window on the "View Page" route in the TYPO3 backend, you can't interact with the previewed website anymore.

Steps to reproduce:
Open TYPO3 Backend => View => choose a random page => change size of window to "Custom" => resize window with mouse

Solution:

in /typo3/sysext/viewpage/Resources/Public/JavaScript/Main.js

change:

      i.default("#viewpage-iframe-cover").remove(), this.persistCurrentPreset(), this.persistCustomPreset()

to:

      i.default("#this-iframe-cover").remove(), this.persistCurrentPreset(), this.persistCustomPreset()