Version: (using KDE 4.1.0) Installed from: Ubuntu Packages Just right-click on a window and select "Configure Window Behavior...". In the KDE Control Module window that opens the window decoration preview just crashes. If I move other windows over the KDE Control Module window the preview area is never repainted. I will attach a screenshot where I moved the GIMP window past the KDE Control Module window. The strange thing I noticed is that this bug affects much less area of the preview window if you start "System Settings -> Appearance -> Windows". There are still some parts not repainted but much less than when the KDE Control Module window shows up alone.
Created attachment 26898 [details] Screenshot showing the crashed window preview
I can confirm drawing errors although I have not been able to get the preview to crash. Some initial valgrinding reveals memory leaks but I haven't seen anything more sinister.
Just to follow up on the valgrind memory leaks, they were all from one-off allocations in style code or Qt/system libraries, no smoking guns in kwindecoration.
I just tested KDE-4.2 beta 1. The preview does not crash any more but the Oxygen preview does not work. The active window title and the stripes are never shown in the preview. I will attach another screenshot.
Created attachment 29161 [details] Screenshot showing the broken Oxygen preview
Closing as the original crash doesn't happen anymore. The drawing bugs (not showing the stripe) are now described in bug 180100
Bulk change: move all KWin kcm bugs to product kwin