Benjamin Berg authored Aug 05, 2019 and Benjamin Berg committed Aug 05, 2019

As gnome-shell is a required component for GNOME sessions, gnome-session
will currently always try to autostart it. However as we are moving towards
using systemd's user instance for session startup, gnome-session should only
be responsible for launching the shell when either not running under systemd
or when we were built without systemd support.

gnome-session can detect the former but not the latter, so communicate this
via the newly added X-GNOME-HiddenUnderSystemd key in the .desktop file.

GNOME/gnome-shell!507
GNOME/gnome-session!13