Running a graphical app in a Docker container, on a remote server

EDIT 2021-09-02: A reader made me realize that the “socat” trick can be greatly improved by adding “,fork” on the server part.
This allows socat to accept multiple consecutive connections, just like a real production server would. In practice, I find
myself using a variation of this trick a lot, but without the ‘socat’. Indeed, if it is acceptable for the container to
open a connection with the host, this easiest is to set X11UseLocalhost=no in /etc/ssh/sshd_config. The rest of
the adaptation is left as an exercise to the reader (said otherwise: I’m too lazy to dive into these scripts…). This reader
also mentionned that the patch to the “Xauthority” could be specified via en environment variable thus allowing to place this
file anywhere and limit assumptions on the container.