With Firefox version 63, I have the problem on YouTube and Netflix, if I snap Firefox in a corner (with mouse or WIN + arrow keys) and switch a video to full screen, left…
With Firefox version 63, I have the problem on YouTube and Netflix, if I snap Firefox in a corner (with mouse or WIN + arrow keys) and switch a video to full screen, left and right is still a few pixels square. In addition, the taskbar is in the foreground (can not be fixed). [IMAGE 1]
If not left, right (top or bottom) snapped then it works, if Firefox is maximized too. The error occurs only in Firefox. Exit Explorer.exe and reboot PC does not work. Error exists since update on the first day of release (early October) - version has been withdrawn by MS,
I also installed the version on my laptop and have been updating ever since.
Apparently the error also occurs with some others: https://www.reddit.com/r/Windows10/comments/9lwzmm/fullscreen_broken_in_october_update/ but it has probably not changed.
Useful data: Windows version 1809 build 17763.134 Graphics driver up to date Firefox completely reinstalled (profile, cache & cookies deleted) even without add-ons started. 2 monitors On the laptop (also tested with 2 monitors) no problems.
I am thankful for every help. Error is really annoying.