Allow duplication of individual monitors
This is something I have been struggling with for a while. My setup is as follows:
I have 4 monitors attached to my system. 3 of them are actually in use, the 4th monitor is my HDMI audio receiver connected to my TV, unrelated to my computer. I do not wish to use the TV with my computer. The easiest solution which worked in other DEs, plus macOS and Windows, is to just mirror the HDMI receiver with my primary screen, while extending the desktop with the other monitors.
Different DEs and OSes have their own way of dealing with this:
- KDE lets you drag monitors on top of each other in the settings app,
- Windows lets you select "Duplicate screen x with y" from a dropdown menu,
- macOS, while holding down Option/alt, lets you drag monitors on top of each other.
In GNOME, to allow this functionality, you must use Xorg and manually use xrandr to generate this configuration. The command would look like this:
xrandr --output DisplayPort-0 --same-as HDMI-3 --output HDMI-0 --left-of DisplayPort-0 --output DVI-1 --right-of DisplayPort-0
Ideally, Mutter and the GNOME Control Center could let the user overlap/duplicate individual monitors.