Created attachment 4193 Screenshot of the bug. This is reproducible everytime: I have a panel at the bottom right of my screen set to auto-grow with 1% width. I have a series of launcher icons and separators before this setup: separator, notification area, separator, workspace switcher, separator, clock, separator, action buttons. If I launch any application with a status icon, the workspace switcher produces a graphical glitch (see attached). This trivial visual artifact disappears the moment I have the workspace switch redraw itself by: opening/moving/closing a window, mousing over it, etc. After correcting it, if I launch another application, it happens again.
This behavior also occurs with the notification area's frame enabled. I've seen this occur while using both the proprietary Nvidia and Nouveau modules.
This widget is totally out of our control so I think this would have to be filed upstream against libwnck. Possibly it's also fixed with libwnck3.