From Fedora Project Wiki

Over the last several releases, the way to configure the system-wide/login screen monitor resolutions, rotations, and geometry has changed several times. You used to be able to configure it in xorg.conf, but then the GNOME RandR plugin changed that. On Fedora 19 the RandR plugin was configured by /etc/gnome-settings-daemon/xrandr/monitors.xml. Now with Fedora 21 it has moved to /var/lib/gdm/.config/monitors.xml. I don't know that there has ever been any user interface for these settings which works system-wide/login-screen (control-center works per-user, but not for gdm/login-screen), and there has been a lack of documentation on how to do this manually. Now with this current change to Wayland, has it been thought about? How will system-wide settings and/or login-screen settings be handled? Will X and Wayland use the same settings? Will there be a UI for this? Will it be documented? Or will I have to grep source code again/run "strings" on binaries to find out how to do it? --User:cra