2018-05-22 13:56 GMT-03:00 Rick Stevens ricks@alldigital.com:
And I just had lightdm screw up royally. First, upon login I got an XFCE polkit error popup, which is singularly useless in telling you anything you can troubleshoot with. Then, I had no access to the sound hardware on my machine, nor could I enable/disable wireless, play with firewall settings or anything else, as polkit thought I didn't have permissions to do anything, nor did it ever pop up an authentication dialog.
OMG, just what happened to me. So lightdm is to blame?
I wiped my xfce settings, reinstalled lightdm, xfce4-polkit and anything else I could think of to no avail. I finally just punted, disabled lightdm and enabled lxdm and everything started working again.
I think I had another DM around. Will switch and see.