Using and Rpi4 with XFCE:
Every time I switch windows the display turns off momentarily or is reset. Let's say i'm in firefox and I click on the thunar window, or the desktop. The screen goes blank for a second, then pops back on.
I've tried both HDMI outputs and I've tried it on 2 different monitors and the condition persists. I've also tried switching out the os for raspian (or whatever it is called now) and it doesn't happen anymore; it works normally.
Also, if I set the WM settings to focus with mouse hover, it happens then too, so it happens during the focus/unfocus, not the clicking or the raising of the window.
It doesn't happen with every window. It doesn't happen with the onboard window(an on-screen keyboard), and it doesn't happen with XFCE terminal.
I tried creating a new user, and the new user has the same problem.
I've skimmed the logs, and don't see anything relevant, but I'll look a little harder.
Any suggestions?