Videos and livestreams are zoomed?

If I want to watch a video on Youtube, they are all zoomed. If I'm lucky, it will be normal after 1 hour if I try again.

For livestreams it has never been zoomed. Or at Netflix, the preview so far only zoomed. I have the problem for exactly 4 days.

Here is a screenshot so you have it in mind:

Press during the playback

Ctrl + 0

Should reset the zoom back to normal view.

Not the page is zoomed, but the video itself. But as I said in many videos it works quite normally. But until today it was zoomed on all livestreams.