Unable to answer "Are these opening hours still correct?" – on floor 0: Mix Markt (Supermarket) – https://osm.org/node/10009604164 via StreetComplete 57.3:

There is a sign saying the oepning hours are PO-NE (MON-SUN) 9:00-20:00... But im here at Sunday 20:58 and the place is still open

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https://westnordost.de/p/231818.jpg