Any examples where it happens?
What version of Opera and OS?

Opera: 45.0.2552.888
Windows 10 Pro
It happens in any site with flash player (flash online wideos flv) for example: kino-dom.org, animevost.org, http://seasonvar.ru, http://kinogo.club, and many more

by from time to time i mean that to open video full screen i need to try to do that few times, and when i will close ful screnn mode i wouldnt be able to restore normal full screen mode.

OS: Windows 10. (on both laptops with this issue) on laptop that works ok WIndows 7
Opera Version: 45.0.2552.888 (PGO)
This problem always happens on www.kino-dom.org and on some other pages it hapens from time to time.

Rarely it manage to open full screen but it is very rare.

I use 2 computers with same version of opera and flash player. On one flash player works in full screen perfectly on second one (laptop with highter resolution) flash wont open full screen and it looks like this http://i.imgur.com/Sccqn.png. The main thing is that this problem happens with any flash video i want to play. And some pages have only flash online video.
I already tried disabling hardware acceleration.
Laptop that work ok, have resolution: 1366x768
Same problem happend on smy previos laptop from work with resolution 1920x1200
Now it happens on laptop with resolution: 3840x2160
Can some one help me with this problem?