Sometimes, Lightdm blinks after auto sleep

[kwg]

This issue is being discussed here:

Xfce lock screen flashes erratically

Did my weekly update on Sunday, with about 85 packages. I use xfce4-screensaver and lock my screen via xfce4-power-manager inactivity timeouts. After my system update and a reboot, the lock screen flashes and is very hard if not impossible to recover from. In several instances I’ve had to ctrl-alt-F2, log in, and kill xfce4-screensaver running under the other login session. It appears that the dialog may not be getting focus and not receiving focus events. Reviewing packages that were updat…