[SbEpUBz2]

KDE disables compositing when SDL apps are opened to improve performance. It should return once the app is closed. You can disable this behavior in System Settings > Display and Monitor > Compositor and unchecking Allow applications to block compositing.

[johnchristopher]

Wow, thank you !

It's not the first time something like that happened to me but I would never have had the patience to investigate !

Can confirm unchecking that setting solved that problem.

[the_pwner224]

This will have very bad effects when playing video games and might(?) potentially increase battery usage when watching full screen videos.

Compositing should only provide the fancy effects like Wobbly Windows and window previews in the alt-tab switcher etc. Not sure why this is causing KWin to crash... You can use Alt-Shift-F12 by default to toggle compositing.

But if you're not doing anything more graphically intense than playing turn-based or slow-paced video games then I guess you can use that option to permanently leave on compositing.