Unable to answer "What’s the surface here?" for https://osm.org/way/451546307 via StreetComplete 53.3:

It is Tartan.

"What???"
The place has gone or never existed. This is an auto-generated note from MAPS.ME application: a user reports a POI that is visible on a map (which can be outdated), but cannot be found on the ground.
POI name: Home
POI types: tourism-artwork
OSM data version: 2019-07-27T07:02:33Z
#mapsme

What kind of business is Modrin d.o.o.?

I feel like this section of Šmartinska has a quite important function in the road network and should be promoted to highway=secondary.

Any thoughts?

"It is planned but is not there"
The place has gone or never existed. A user of Organic Maps application has reported that the POI was visible on the map (see snapshot date below), but was not found on the ground.
OSM snapshot date: 2022-10-29T18:47:05Z
POI name: projekt: Fakulteta za strojništvo
POI types: building
#organicmaps

I've interpolated housenumbers Povšetova 21-29 from neighbouring buildings. Can someone please verify on the ground?

AED outside 24/7

New pier / wave breaker construction