The user Nata37 posted a question in this forum on Fri Apr 21, 2023 3:10 am.
See
viewtopic.php?p=210953
I have pasted the two sets of marks into one picture below, with the marks from Nata37 on the left and the stamps on my plate on the right:

It seems that the Bern city mark (or pseudo-mark) on Nata37's piece and mine are identical, down to the smallest details visible.