This is not a new bug but it’s worth updating to reflect the changes with Full offline mode.
In the past, when playing offline, leaving the game placed the user at the Login screen and not the character selection screen. This is still happening, even though it says otherwise:
With Full Offline the user is taken to the Offline screen:
I don’t believe this is an OS issue as I’ve seen this on Windows systems. That said, I use OpenSUSE Tumbleweed.