The silicone seal of the window has numerous unsightly deposits

Hello everyone,

unfortunately the pictures are very blurry, but I really hope that the experts among you can still tell me what this is about.

Thank you in advance and have a nice Pentecost

At first glance and solely based on the pictures, my thought would be that it is mold!

Looks a lot like mold to me as well - at least that's what the photos suggest. Can the stains be wiped off (at least partially)?

It also looks a lot like mold to me - at least that's what the photos suggest. Can the spots be wiped off (at least partially)?

I didn't try that when I viewed the apartment.

I also believe that this is mold. That means the window installation here (by today's standards) is defective or the window frame has a very poor U-value. This causes condensation to form there.

I also believe that this is mold. That means the window installation here is (by today's standards) faulty or the window frame has a very poor U-value. This causes condensation to form there.

Unfortunately, this is a new building, completed last year.