As it turns out the issue is caused by authd refusing access to all non- root users: https://github.com/ubuntu/authd/issues/856
I don't actually need authd so in my case removing it was sufficient to resolve the issue. However I expect anyone who uses both authd and KDE to still encounter this issue. ** Bug watch added: github.com/ubuntu/authd/issues #856 https://github.com/ubuntu/authd/issues/856 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2118925 Title: kscreenlocker_greet stuck due to permissions To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kscreenlocker/+bug/2118925/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
