After a one hour technical telephone interview, I was invited onsite to Munich for another one hour interview.
The two interviewers were very friendly and I answered all questions to their satisfaction - most of them were related to my CV with a small technical portion in the end.
I actually had a very good impression with the interview itself, although the questions sometimes were a bit vague.
Feedback was promised to get to me after 1-2 weeks, for which I gladly waited. Since there still wasn't any feedback by the recruiter after 3 weeks, I got back to them, to which the recruiter answered that the team will get back to me shortly, since they are still doing interviews.
I waited 2 more weeks, asked again for some kind of feedback, to which I got no reply at all - and still haven't after asking again after 2 more weeks.
It's actually a very rude practice to invite candidates onsite and ghost them after their interview - I haven't had that kind of a bad experience in the hiring process of any company so far and I will definitely not recommend applying there.