I have just had this issue as well, I have 3 displays: Internal Panel (Disabled) 27" on HDMI (Active) 27" on VGA (Active)
I managed to work around the problem by activating the internal panel so it shows all 3 displays then I could drag the displays into the desired layout. Before applying the changes I turned the internal panel off again as I didn't require it but it saved fine. System Details: DELL XPS 9560 running Ubuntu 17.10 External DELL Dock (TB16) with the displays attached -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1724955 Title: unable to drag monitors in Display Arrangement To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1724955/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs