@robert - I've seen reports from xubuntu testers where it was sometimes working. So I tried more on a completely brand new installation.
Lock - unlock fails - this continued for 3 attempts at which point I reached desktop.
Lock and unlock cycle next time took 2 attempts.
Lock and unlock cycle next time took 1 attempt.
I was then able to lock and unlock at will.
Attached all /var/log/lightdm logs from that session.
@robert - I've seen reports from xubuntu testers where it was sometimes working. So I tried more on a completely brand new installation.
Lock - unlock fails - this continued for 3 attempts at which point I reached desktop.
Lock and unlock cycle next time took 2 attempts.
Lock and unlock cycle next time took 1 attempt.
I was then able to lock and unlock at will.
Attached all /var/log/lightdm logs from that session.