Screen lock is locked down, not locking
I can't get one fedora 28 system to lock from the keyboard Super+L I am not sure what I configured wrong.
I checked gconf settings: gconf settings > Devices > Keyboard > Lock screen = Super+L
and watch the logs: journalctl -f
gnome-shell[2121]: Screen lock is locked down, not locking
I searched the archives also but did not find this issue covered.