wenn's so ist, dann wäre es doch super wenn du es auch gleich änderst!

I totally agree with this definition. As already mentioned the street tag 'sidewalk' means that the street has a sidewalk and that is not extra drawn in the map!
In this particular case we have a sidewalk and a street. Hence, that tag of the street should be 'no sidewalk'. Otherwise we have two! That's my understanding. If you have the feeling that this is wrong its up to you to change this. I'm not living Gdansk and so I would not be confused to find two sidewalks on this place. :-)

Sorry. That was a question from StreetComplete.

My understanding is a bit different to this point. If a street has a tag 'sidewalk' then there is no additional sidewalk draw. Hence, in this situation the sidewalk is drawn separate and is about 1m (or it was even more) separated from the street. So the correct tag is 'no sidewalk'

Hallo, da steht ein Geschindigkeitsbegrenzungsschild von 50 am Anfang der Strasse. Hab' das mal eingetragen.
Fahrradweg und Bürgersteig gibt es dort nicht. ;-(
Gruß,