This is very likely not a bug in xfce4-power-manager, because when you log out/switch users /lock your session, you're going to a new VT, which means the default X11 settings are being used and xfce4-power-manager isn't running there (at least not at the greeter, it's only being started in the session).
Odd that you cannot change your brightness anymore within the session, I could also imagine that there are some driver issues. I presume this issue persists? -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1384515 Title: Laptop screen dims on logout To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xfce4-power-manager/+bug/1384515/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs