Today I had some windows open in workspace 1 and in the workspace below it I had VLC open. When I clicked on the VLC sidebar icon when I was in workspace 1 the window moved up to workspace 1, but it was pushed far into the left of the screen of workspace 1 (as in this question). I tried resizing the window (since I was unaware that I could just alt+click to move it out) to get it out of there and the window behaved oddly, changing orange as if it were maximizing, but the outline stayed the same. After that, if I recall correctly, I had to close VLC because it froze. Now when I open VLC the outline of the window appears, but it never gets to the point of functionality. The outline flickers, and when I mouse over menus or sidebar icons they appear and don't go away. The first time it happened, I got a popup window that said Compiz crashed, and I think I can safely assume that was the reason the borders disappeared from all the windows of all open programs.
I've looked up some related issues through regular bug reporting channels, and I have a feeling something like this wouldn't get fixed anytime soon. Not that I mind filing a bug report, mind you.
My question is: since I can't use VLC right now, and I'd really like to, is there any way I can delete or reset VLC's window position data? I have good reason to believe that it's only VLC on my machine that is affected by this bug, so fixing this data, wherever it is, will likely fix the problem. I just don't know how to find it.