Ik vond het volgende op een forum:
"
Boot into recovery... to the command line.
Type the following (replacing "[yourname]" with your user name, of course):
nano /home/[yourname]/.kde/share/config/kwinrc
Find the this line under the heading "Compositing":
Enabled=true
Change it to:
Enable=false
Then press Ctrl+X. Press Y. Press Enter.
Type:
reboot
And then log into KDE normally.
"
