Kolourpaint version 4.10.2 on KDE 4.10.5.  This is likely an upstream bug, but I don't know WHERE upstream, so that's why I'm filing here.  I reproduce a similar problem in Kompare, but can't reproduce it in any of the other dozen or so applications I've tried.  This also appears to be a regressive bug, as I was unable to reproduce it on a machine running Precise (12.04) but it reproduces on another Raring (13.04) machine.

Reproducible: Always

Steps to Reproduce:
1. Open Kolourpaint (or Kompare)
2. Move the mouse cursor over one of the menu options (e.g. "File").  The option fades to a darker gray as if depressed.  Now move the mouse cursor away.  The menu quickly fades back to normal lighter gray.  (Colors described assume the default color scheme.)  This is normal correct functioning.
3. Now, move to mouse cursor to hover over the "File" menu, but move the mouse cursor over the adjacent menu (i.e. "Edit") on your way there.  File menu will appear depressed as normal, but the "Edit" menu will not have completely faded back to normal light gray.
(You may need to do it a few times to get the correct timing, but it's not hard to reproduce.)



It's not limited to only the adjacent menu option - it can be any of them the cursor has passed over on its way to the destination at varying degrees of fade depending on the precise timing employed.  The delayed fade survives clicking the other menu and perusing its options.  (see screenshots)