Same issue here.
I am guessing xfce4-screensaver should conflict with and remove light-locker when its installed as suggested in a comment above.
Updated from Ubuntu + Xfce (xubuntu-desktop) 18.04 -> 20.04.1. Used work around like Craig above, and disabled lock part in xfce4-screensaver.
Same issue here.
I am guessing xfce4-screensaver should conflict with and remove light-locker when its installed as suggested in a comment above.
Updated from Ubuntu + Xfce (xubuntu-desktop) 18.04 -> 20.04.1. Used work around like Craig above, and disabled lock part in xfce4-screensaver.