Hey all, I've got an unusual problem; I have Kubuntu installed on a laptop, and it works great as long as I have an external monitor plugged in. However, whenever I boot or resume without an external monitor, KDE seems to work for a second or two, then the screen dims and the mouse cursor visibly locks in place, although can still be used invisibly.

Other notes:
If I plug in an external monitor when it is in this locked place, the screen brightens and the mouse cursor starts working, even if I then disconnect the external monitor or if the monitor is disabled in settings.
Everything works great in other desktop environments

no idea but can you test a new user to see if its a corrupt/bad rc (config) file

Hrm, you seem to be on to something, a new user does not show this bug. Any idea what config file might cause this? I was thinking some sort of power management problem, considering the screen dims, but nothing leapt out at me from the options...

you can try renaming the follow 3 files, really no idea why they'd cause the problem or what the problem is.

location:

if running KDE 4 ~/.kde[4]/share/config
if 5 ~/.config

files:

kwinrc
kcminputrc
kaccessrc

then restarting KDE

No luck, still getting the same problem on my main user account...

Worst case, I could just abandon my old user, but it would be nice if I didn't have to...

clueless, try changing the mouse cursor used - yea I just throw things against the wall hoping something sticks

try disabling compositing alt+shift+F12

chances are its a ~/.config/k* file

moved to Kwin forum (guessing it would be more appropriate)

Not solved, per se, but upgrading to Plasma 5 fixed the problem.