Postby erwan10 » 07 Sep 2015 11:59
The short answer would be to file a bug report (with thorough description of the Window Manager brand and version as you did here)
The long answer is that, from an application perspective in a X11 environment, requesting full screen is done via the ICCCM standard. And, in last resort, the Window Manager (Gnome shell, Unity, KWin, Mate, Cinnamon, xfce, .... they are galore) is the one to eventually decide what to do or not to do with this request. Some Window Managers just accept the full screen request without any restrictions. Others put extra (often undocumented and definitely not described in the ICCCM standard) restrictions to what type of window is eligible for full screen, or whether some other part of the shell should still be displayed on top or what the useful surface of fullscreen should be. So the only thing to do is to find out what specific requirements this particular Gnome shell 3.14.1 expect for a full untainted fullscreen and code it ! When using the default vlc based on the Qt library, this usually works fine, because the underlying Qt library does provide these extra properties for most Window Managers.