Comment # 6 on bug 1176229 from Wolfgang Bauer

(In reply to Dirk S. from comment #5)
> Looks like kwin failed to start/crashed.
> /usr/bin/kwin_x11 is running
> Did you reboot after the last update?
> yes
> Does it work on a fresh user account?
> yes

Ok, so it's not a general problem.

> What happens if you run kwin_x11 in konsole inside the running user session?
> I.e. what output do you get?
> kwin: unable to claim manager selection, another wm running? (try using
> --replace)

That means that kwin was already running...

Did you try that on the new account?
I actually wanted to see the output from the session where it was failing to
start.

> What displaymanager are you using?
> I have no changed anything. I don't know.

So let's assume it's sddm.

I only asked because I noticed a problem with kdm in Plasma 5.19.5 (a fix for
that is pending).
But then kwin should still start anyway...

> I've rename the home directory and created a new one. Now it is working
> again. Any idea what files should I compare to find out what happened?
~/.config/kwinrc would be the first thing I'd imagine.

Could you please try to move everything back except this one please?