> Could you please post snapshots of these artefacts?  If possible,
 > please post several ones that show how the artefacts are added as you
 > move downwards through the menu by pressing C-n or the down-arrow.

Attached.  The first three are after a down-arrow.  <1> is after the
first artefact appears in the echo area.  <2> is after moving from "--"
to "Print Buffer", <3> after one more down-arrow from <2>.

To get more artefacts in the right half I apparently have to do up-arrow
as well.  <4> is after moving up from "--" to "PostScript Print Region".
<5> - <7> depict the situation after a few more up/down movements.

martin