@naheed Tried each one of it, I even tried deleting the browser and installing it back again. It didn't help. Now, Turns out one of my friend started having the same issue. There are more subjects are created about the problem there is definitely a problem with the adblocker.

I'm having the same issue on the normal version of Opera. Disabling ad-block fixes the issue. Ad-blocker had problems just like @j0hnym explained. The first ad at the beginning of the videos were being shown.

I even formatted all my disks and re-installed Windows. The problem remains. Why nobody is responding?

I tried cleaning the cache and cookies and everything on the CTRL+H menu.
I turned off any kind of firewall, anti-virus.
I turned off Ad-blocker.

None of them helped me solve the problem.

Hello! This problem started appearing lately. I'm having this problem mostly on youtube, some videos won't go fullscreen and some will. When the problem appears I can't see recommended videos and etc. All the screen is white I only can see the video window and when I click on fullscreen button it reacts like I pressed F11 key but the video wont go fullscreen.

It looks like this. Thanks in advance!