I just tested something, and it turns out that the issue was I had the Extensions turned on (even though each extension itself was off, as in the picture). Once I toggled that off, the issue resolved itself and now locking appears to work perfectly. Not sure why having extensions on would cause this behavior, though.
** Attachment added: "Screenshot from 2018-11-19 00-09-47.png" https://bugs.launchpad.net/ubuntu/+source/gdm3/+bug/1803807/+attachment/5214087/+files/Screenshot%20from%202018-11-19%2000-09-47.png -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1803807 Title: Lock screen doesn't hide the screen contents To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gdm3/+bug/1803807/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
