bug#24090: 25.1; toggle-frame-fullscreen breaks UI features in Gnome

[martin rudalics <rudalics@gmx.at>]

 > With RC1 (from the tarball), when I have an Emacs frame in the
 > "fullscreen" state (using M-x toggle-frame-fullscreen RET) (i.e. the
 > frame fills my monitor and the title bar is hidden), two user interface
 > features in Gnome are broken. The two features are:
 >
 > 1) Normally, when I move my mouse cursor to the top of my display, the
 > Gnome top bar, which I keep hidden, drops down into view (in front of
 > all other windows).
 >
 > 2) Normally, when I move the mouse cursor to the top left corner of my
 > display (the "hot corner") a gallery of all my windows is shown and
 > various user interface features are provided for controlling the desktop
 > environment. (This "feature" is very annoying but I've never got around
 > to turning it off.)
 >
 > The bug is that with an Emacs frame in the "fullscreen" state, nothing
 > in particular happens when I move my mouse cursor to the top of the
 > screen or to the top left corner.

FWIW Gnome's top bar and your gallery of windows should be of type
_NET_WM_TYPE_DOCK and are therefore shown _below_ your Emacs 'fullboth'
frame which should be of type _NET_WM_STATE_FULLSCREEN.  So I don't see
a bug here.

 > This happens when the "fullscreen" Emacs frame is the active window in
 > Gnome, and also when a window of another application is the active
 > window if the window of the other application is not maximised. But if a
 > window of another application is active and maximised (i.e. is in front
 > of and hides the Emacs "fullscreen" frame), then the Gnome UI features
 > work as usual.

Do other applications (e.g. Firefox after hitting F11) behave
differently when they are in fullscreen mode?

martin