I received a new answer right now

echo $WAYLAND_DISPLAY (if it outputs "wayland-0" or something it's a
Wayland session),
or echo $XDG_SESSION_TYPE

I don't know how and why these variables should be set on GuixSD but people
on the fediverse don't know that I asked on behalf of you ☺


Il giorno ven 4 gen 2019 alle ore 12:52 Catonano <catonano@gmail.com> ha
scritto:

> another answer arrived rigt now
>
> If you open xeyes, the eyes will not move if your pointer is on top of a
> Wayland window.
>
> Also, the combination
>
> Alt+F2
>
> and then
>
> R + return
>
> restarts Gnome if it's on X. It doesn't if it's on Wayland
>
>
>