Ubuntu 16.04 Mate vlc info boxes appear on wrong monitor

[technomage bruce]

  On a multi-monitor Ubuntu 16.04 system the VLC pop up info boxes appear on the wrong monitor - see attached screen shot. 5 monitor, 3 gpu, compiz (with accelerated graphis), xinerama - two monitors are clones, two other monitors are rotated. As you can tell from the description and attached screen shot this is an unusual monitor set up, so I would not be surprised that this issue hasn't been seen before. I'm rather excited as this is the first Ubuntu/Mate desktop multi-monitor set up that I've gotten to work with compiz and accelerated graphics (I should say that Mate is the only desktop environment that I got working with multi-gpu/monitors and compiz/accelerated graphics) and I've only encountered minor bugs like this.

  As you can see from the attached screen shot, the mouse is hovering over the OpenGL GLX box in the VLC preferences window (bottom, center monitor). The pop up info box appears on the upper section of the left most monitor. If I were to move the VLC preference window, the info pop up box offset would be the same. For example, if I move the preference window 100 pixels to the right, the info pop up box would also appear 100 pixels to the right of its previous position.

[Sebastian Ramacher (s-ramacher)]

The pop up is handled by Qt, so reassigning there.