Comment # 8 on bug 1234469 from Stefan Hundhammer

So it looks like your 'sudo' environment changed with one of those recent
updates. In general, ony of 'kdesu' or 'gnomesu' (or 'xdg-su' which is an
elaborate alias for them) is recommended to start a GUI program with root
permissions on your user desktop. AFAIK the major desktops use those to start
YaST Qt (or other GUI programs that need root permissions) from the menus. But
when you try the same from a command line, you need to invoke them manually, of
course.

'sudo' can work, but only if you tweaked your 'sudo' configuration in
/etc/sudoers to keep some environment variables like $DISPLAY; the default
'sudo' setup is to forget almost all of them. That may be more secure, but it's
a royal PITA; it's an unneccessary incentive for users to work more, not less,
with root permissions.

'su' behaves a bit differently; IIRC it doesn't just kill your carefully set up
environment the way 'sudo' does. That might be just that little difference that
made it work for you.


But there are also the permissions of the desktop itself. X11 has elaborate
methods to close it even to root processes, so you need to open it a bit to let
a root GUI program use it (both ways, displaying the GUI and receiving input
from your keyboard and mouse). There is the old general 'xhost +' command which
all security experts advise against.

I am sure Wayland has equivalent methods, but I have been a happy X11 user
since about 1990, so I don't know much about that.


But please try 'kdesu' (on KDE) or 'gnomesu' (on GNOME or Xfce) first. That
should do the trick.


But anyway, this is not a problem on the YaST level.