$ sudo su
root@mycomputer:/home/me# gedit
No protocol specified
Unable to init server: Could not connect: Connection refused
(gedit:4492): Gtk-WARNING **: cannot open display: :0
=====
And that's the problem here. When gparted is ported to gtk3, the xhost workaround will stop working. And there's no incentive for GNOME to fix apps to run as root under XWayland, if they won't be able to under Wayland. GNOME wants to *encourage* apps to upgrade from gtk2 to gtk3 to get native Wayland support, better HiDPI support and several other features and improvements.
$ sudo su :/home/ me# gedit
root@mycomputer
No protocol specified
Unable to init server: Could not connect: Connection refused
(gedit:4492): Gtk-WARNING **: cannot open display: :0
=====
And that's the problem here. When gparted is ported to gtk3, the xhost workaround will stop working. And there's no incentive for GNOME to fix apps to run as root under XWayland, if they won't be able to under Wayland. GNOME wants to *encourage* apps to upgrade from gtk2 to gtk3 to get native Wayland support, better HiDPI support and several other features and improvements.
Therefore, I'm closing this bug. Sorry.