KDE 4.6 Taskmanager popup picture

When I hover over an open programme which is on the task bar I get a pop up, but instead of a picture of the actually programme I get a grey box like this


Any ideas how to fix this. Thanks

You could turn off those ‘Taskbar Thumbnails’ in ‘Personal Settings > Desktop Effects > All Effects’.

Or you could try different settings in ‘Personal Settings > Desktop Effects > Advanced’. ‘Keep Window Thumbnails’ and ‘Scale Method’ sound promising.

Try a different theme. I find oxygen or slim-glow fairly compatible with most stuff.

Fiddling in personal settings managed to kill the graphical pop up completely - reverting back to the standard tool tips. Changing the theme had no effect at all - I was already using slim-glow. Any other ideas gratefully accepted.