"Click for connected devices" shown in full screen mode and is not removable

Hey! Once when I was watching video on YouTube I have clicked some buttons on keyboard, and it stopped responding on anything (clicks, clicks like "f" to quit full screen mode, etc). I have closed the safari window, reopened it and it removed unavailability to not do anything, but now I have a pop up when I watch anything in full screen. I will attach the screenshot how does it look like.

Btw, its not attached only to Safari, it is also shown in other browsers.

MacBook Pro m3 pro.

Thanks :)