what you describe there seems normal and not buggy, the second server is the greeter one, if you select your first user and enter its password you should be back to your user unlocked (the greeter acts like the locking screen when going back) and only one xserver
what you describe there seems normal and not buggy, the second server is the greeter one, if you select your first user and enter its password you should be back to your user unlocked (the greeter acts like the locking screen when going back) and only one xserver