Mold on joints due to condensation water?

Hello,

is this mold concerning or is it normal because of condensation?

Condensation forms at the coldest spot in the room, which is the windowpane. I think the water then runs down into the joint and molds there.

Is that correct or should I be worried?

I have attached photos....

Hello,

...is this mold concerning or is it normal due to condensation water.

Concerning, mold is not normal.

... I think the water then runs down into the joint and molds there.

That's correct, but how does the water run "uphill"? Picture 1 left corner!
The reveals, lintels, and parapets of the dormer in the roof covering are thermal bridges and require careful execution (insulation => DIN 4108). If this is neglected, the problems described here occur.

Best regards

Cut out the old joint yesterday and looked underneath. Nothing to see. So it was just surface mold. I’m relieved for now...

Renewed the joint, cleaned everything with bleach cleaner.

From now on, I will always wipe dry after showering and ventilate more.

Then nothing should happen again.