Sl�vek Banko composed on 2019-02-05 01:06 (UTC+0100):

> First, for XAUTHORITY should be: XAUTHORITY=/var/run/xauth/A${DISPLAY}-*

This works:
DISPLAY=:0 XAUTHORITY=/var/run/xauth/A${DISPLAY}-msFdGa import -window root iitdm.png

These do not
DISPLAY=:0 XAUTHORITY=/var/run/xauth/A${DISPLAY}-* import -window root iitdm.png
DISPLAY=:0 XAUTHORITY=/var/run/xauth/A${DISPLAY}* import -window root iitdm.png

Of course, the one that does work requires lookup of the content of /var/run/xauth/ after a reboot.

> Second, I do not see in the man page that xwd would accept the environment 
> variable XAUTHORITY or option like -auth or -xauth.

I don't know why the URL I was working from used xwd instead of import.

Another URL that fails to provide a way that works, it too is for gdm:
https://www.howtoforge.com/how-to-take-a-screenshot-of-your-login-screen

Search on kde.org only found shooting desktop with Spectacle, not greeter.
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