Extra monitor detected that doesn't exist

[Luke Berwick]

I have a two monitor setup, but a third display is present in system settings>displays. The third display is labeled Unknown display and is given a default resolution of 1024 x 768 (4:3). System seems to detect something is wrong because after I unchecked the Use This Display toggle I could not check it again. I have a secondary monitor to the left of my primary monitor, but in Displays the extra unknown display shows up as the rightmost monitor. Until I disabled the third display I would lose my mouse cursor from time to time whenever I went off the rightmost edge of my primary monitor (as it was moving to the third display).