This turns out not to be a bug, but simply a different (and, it turns out, a much improved) interface for the same purposes. I apologize for the haste (also, I could not find a way to simply rescind it).
** Changed in: gnome-control-center (Ubuntu) Status: Incomplete => Invalid ** Converted to question: https://answers.launchpad.net/ubuntu/+source/gnome-control-center/+question/660501 -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-control-center in Ubuntu. https://bugs.launchpad.net/bugs/1730149 Title: No option to set a 2nd display as mirrored in Ubuntu 17.10 Status in gnome-control-center package in Ubuntu: Invalid Bug description: Up to rel 17.04, we were able to choose the mode for a second display as either "mirrored" or "extended". With rel 17.10, it always defaults to "extended". To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-control-center/+bug/1730149/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp