Comment 29 for bug 1713313

@Norbert

the full solution is not so easy; so be patient.
Several thinks can be done:
- run xhost script into a terminal each time a session is opened
- insert the xhost script into .bashrc file
- and/or test some more propositions:
   * https://unix.stackexchange.com/questions/317282/set-environment-variables-for-gnome-on-wayland-and-bash-on-virtual-terminals-or#326161
   * https://ask.fedoraproject.org/en/question/108631/running-command-after-gnome-login/
   * https://unix.stackexchange.com/questions/118811/why-cant-i-run-gui-apps-from-root-no-protocol-specified

And for non techy people or those still satisfied with X, then choose X at login time (still prefer lightdm myself for the moment)