TinyMCE: Configure iframe sandboxing to allow YouTube domains

In TinyMCE 6.8.1 (the WYSIWYG editor used by Bludit) iframe sandboxing was introduced. This automatically adds the sandbox="" parameter to all inserted <iframe>-tags. This blocks all embedded videos from playing, even when the CSP-Headers are correct. As I just wanted to write a short blogpost about a YouTube video which discusses why we Germans are able to eat raw pork ("Mett") and suddenly the video wasn't displayed in the editor-view. Browser console showed no problems with CSP-Headers and so I was left to searching.. YouTube gave me the following <iframe> block for embedding the video: <iframe width="560" height="315" src="https://www.youtube-nocookie.com/embed/azdV7EzP0v4?si=sKj7zfe0OkVNxjsi" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" referrerpolicy="strict-origin-when-cross-origin" allowfullscreen> </iframe> However, after copy&pasting that into the TinyMCE in Bludit and…