Related question, since we're on the topic: does Linux have a way to split a single wide monitor into smaller "virtual" monitors?
For example, splitting a 5120x1440 monitor into three:
xrandr --setmonitor DisplayPort-0-0 1280/297x1440/340+0+0 none
xrandr --setmonitor DisplayPort-0-1 2560/595x1440/340+1280+0 none
xrandr --setmonitor DisplayPort-0-2 1280/297x1440/340+3840+0 none