Fullscreen controller causes panel to show above video in MATE desktop environment
When playing a video fullscreen, if the mouse is moved such that the fullscreen controller appears then the desktop environment's panel appears above the video window. Once the controller has hidden again, the panel remains visible until the video window is clicked on to bring it back in front of the panel.
I have tested that the issue occurs with VLC 3.0.4 on Ubuntu MATE 18.04 with MATE version 1.20.1 and VLC 3.0.6 on Arch with MATE version 1.20.4. The issue does not occur with VLC 3.0.1 on the aforementioned Ubuntu MATE version.
As I was preparing this bug report, I found that with some configurations the panel may not appear however the fullscreen controller appears in the wrong place (as though space was reserved for the panel) and VLC loses focus and does not respond to keyboard commands unless the video window is clicked on to focus it again.
I suspect that this bug was most likely introduced by commit ee8c6e5d as this commit falls between 3.0.1 and 3.0.4 and relates directly to the fullscreen controller although I have not confirmed this for certain. I would expect that similar issues may occur when using other desktop environments.
Fixing the issue should be a matter of reverting the commit in question although I'm not sure how this relates to issue #8712 (closed) for which the commit was originally added. IMO this is a more breaking issue than #8712 (closed) (as playing a fullscreen video while working with something else in front is a far less common use case than playing a fullscreen video in the foreground and is a use case that can more easily be met by maximising the player) and #8712 (closed) still occurs for me in version 3.0.6 anyway.
Steps to reproduce:
- Install VLC version 3.0.4 or later alongside the MATE desktop environment.
- Play a video.
- While the video is playing (or paused), switch to fullscreen mode using either the keyboard or the mouse controls.
- Move the mouse so that the fullscreen controller appears.
- Observe that the desktop environment's panel is displayed above the video and/or the fullscreen controller is positioned in a manner to reserve space for the panel.
- Wait for the fullscreen controller to hide.
- Observe that the panel remains visible and/or VLC does not respond to keyboard commands.
- Without moving the mouse, click on the video.
- Observe that the panel "disappears" (is behind the video window where it is supposed to be) and VLC responds to keyboard commands as normal.
Not sure if I need to report the bug against both 3.0.x and master. I've reported it against 3.0.x as that is where I found it and I haven't tested master but I don't see why it wouldn't affect master as well.