Bug#906799: gnome-control-center: crashes or shows blank window when started outside GNOME

[Simon McVittie]

Control: retitle -1 gnome-control-center: crashes or shows blank window when started outside GNOME
Control: severity -1 normal
Control: found -1 1:3.28.2-1

On Tue, 21 Aug 2018 at 08:16:25 +0100, Simon McVittie wrote:
> While trying to reproduce #906750 I found that gnome-control-center from
> experimental doesn't start in a qemu VM

This is because I was starting it from outside a GNOME session (to try
to reproduce a crash that happens when Recommends were not installed, I
launched it in openbox or from a ssh session), and it respects OnlyShowIn
when deciding which panels to show. If the desktop environment is neither
GNOME nor Unity, then it doesn't show any, but then (in the experimental
version) manipulating the visibility of the wifi panel assumes that panel
is available and causes a crash.

The version in unstable doesn't crash, but it also doesn't show any
panels.

Mitigation: the menu entry for gnome-control-center itself won't show
in a non-GNOME session either (due to its use of OnlyShowIn), so this
is not something that is really supported or meant to work.

A possible workaround would be: if any panels would be shown on the
current desktop environment, proceed with that subset of panels, but if
no panels would be shown, show all of them (or those that would show in
a GNOME session) instead.

    smcv