I have two invasions going on!
the one here: identification request - tiny flies invasion
and this one:
We are in Berlin, Germany. This fly is 2.5mm long vs 1mm wide, and seems to like the dark and colder area of the apartment. They arrived at the same time as the tiny ones in the other link, but they don't look similar, so I don't think this is the adult form of the other kind but maybe I'm wrong.
They came with the heat, looking for shelter.