Sluggish window switching in fullscreen mode

When I enter fullscreen mode and try switching windows (ALT-TAB), everything is really slow. Sometimes I even get a black screen for a few seconds. Really annoying. Enyone have the same? When I’m in normal maximized view, no such problems exist.

Tested with Win10 (64), with multiple video cards (GTX670 and cheap integrated ones). Latest daily builds.

Hello, I know this is quite old, but I’ve got the same problem on the lates version (2.83.3).
As you described, when switching windows with ALT-TAB (windows 10) it takes a while before showing blender, as if the pc becomes frozen for a couple seconds, and again as @dddstudio said it happens only in fullscreen mode, whereas in normal mode works perfectly fine. Has this problem been solved /notified or just acknowledged since 2018 ?

P.S. This was the best result I found when googling this problem, that’s why I’m asking here