Created attachment 108630 [details] screenshot Run CS GO in fullscreen mode Alt-tab to the desktop The panel will have the grey color and the state that was before game launching (all applets, clock and widgets do not receive graphics update). See the screenshot Maybe this is reproducible with Dota 2, which is source engine too but free in steam store. I'll try it when it will be downloaded. As you see on the screenshot the hover does work and the panel too, but the panels "frontend" does not.
Yes, same applies to dota2
*** This bug has been marked as a duplicate of bug 353983 ***