"screen appears" means GNOME Shell (Ubuntu desktop) appears.
Following results of ps is executed in ssh console.
No crash file of gnome-shell exists in /var/crash.
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Power on => GDM is displayed:
$ ps -ef|grep gnome
gdm 13761294 0 10:07 tty1 00:00:0
I have the same issue when login via xrdp as well as local login.
When this issue occurs, login via ssh, and execute following command.
$ DISPLAY=:10 timeout 1 xmessage -iconic x
Right after execute it, screen appears.
Other x11-apps works as well, e.g. xclock, xeyes, xcalc...
xrefresh does not
