Version: (using Devel) OS: Linux Installed from: Compiled sources This is KDE SC from trunk, using Qt 4.6.0 Not sure hos it's possible but.. Anyway, steps to reproduce (my case): 1. Ensure panel is on the bottom of the screen (may not be related). 2. Make sure some icons are in system tray. (screenshot1) 3. Click 'Show hidden icons' button on system tray applet. 4. Notice a little flickering just on the right - outside of system tray area (system tray icons are being drawn on neighbouring plasma widget). 5. In my case (may be related to disabled compositing) it's not just flickering, but this icon stays there (screenshot2) and should not have even been attempted to be drawn there. At least flickering reproduced with clean account.
Created attachment 39528 [details] screenshot1 - (icons hidden)
Created attachment 39529 [details] screenshot2 - (hidden icons shown - icon drawn in forbidden area)
*** This bug has been marked as a duplicate of bug 219709 ***