I faced this problem on two different machines (both lightdm + plasma desktop, on both I happily used this combination on Ubuntu 16.04 but once I upgraded to 18.04, or soon afterwards, I lost all my groups).
Switched to sddm on both, it helped. So mayhaps lightdm should be dropped or downgraded, the issue (https://whatstatus.co/guess-ill-die) is fairly critical (usb doesn't work, sudo has issues, pluggable devices don't work). -- You received this bug notification because you are a member of Kubuntu Bugs, which is subscribed to kwallet-pam in Ubuntu. https://bugs.launchpad.net/bugs/1781418 Title: User not being initialized correctly on login To manage notifications about this bug go to: https://bugs.launchpad.net/lightdm/+bug/1781418/+subscriptions -- kubuntu-bugs mailing list firstname.lastname@example.org https://lists.ubuntu.com/mailman/listinfo/kubuntu-bugs