Reverting lightdm back to 1.18.2-2 didn't help. Also I wasn't able to unlock per #846278 using 'loginctl unlock-session {X}', however my init is sysvinit, so maybe that's an issue.
- Bug#846661: light-locker: screen remains black after unl... Gedalya
- Bug#846661: light-locker: screen remains black afte... Gedalya
- Bug#846661: [Pkg-xfce-devel] Bug#846661: light-... Yves-Alexis Perez