When trying to access https://beta.musicbrainz.org/doc/relationship-types/46191a34-84d4-48ff-9c2a-c86d614bc0e3 (which should contain documentation for the "A held concert at P" relationship, linked from the add/edit relationship dialogue), I get a page-not-found error:

Sorry, "relationship-types/46191a34-84d4-48ff-9c2a-c86d614bc0e3" is not a valid documentation page.

It's the same for all relationship types I tested, not specific to places.