I found it necessary to lock+suspend the screen before closing the lid. So I did it with a script tied to the keyboard shortcut CTRL+SUPER+DELETE:
https://askubuntu.com/a/1162665/297529 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1783895 Title: Screen locking fails on Suspend/Resume for laptop lid-switch To manage notifications about this bug go to: https://bugs.launchpad.net/xfce4-session/+bug/1783895/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
