Ah, I see you added https://www.stadt-zuerich.ch/site/velo/de/index/erfolgreich-umgesetzt.html as a source in another changeset.

I uploaded a picture from today here with the signage I meant: https://panoramax.openstreetmap.fr/#background=streets&focus=pic&map=17.56/47.373961/8.538319&pic=bd77e8b4-bca6-46ef-b9b1-9645e45df31f&speed=250&xyz=0.00/0.00/0

Looking at the other signage along Bahnhofstrasse, I think one might be supposed to go on the sidewalk, but not on the street? I'm still figuring it out, let me know if you know more.