Comment 44 for bug 2020782

I can reproduce "other monitors getting turned on at Revert" using upstream Mutter on Xorg. Seems it's something of a feature because Mutter only supports:

 (a) An explicit monitor layout in ~/.config/monitors.xml ; or
 (b) An implicit monitor layout where everything gets turned on and arranged linearly.

There is no third option:

 (c) A detected monitor layout from xrandr when ~/.config/monitors.xml doesn't exist yet (no config ever applied yet).

So I can see this being low priority to upstream and it probably only matters to Xdcv, but it is an upstream Mutter bug/feature.