Thanks for your quick reply 🙂
It is indeed not in the stack. (I took the screenshots just incase I was not able to fix it and wanted to revisit this problem, and thus after I applied it).
But as mentioned, I tried to fix it by removing the “bad” side, and re-applying the mirror modifier without any succes. Also apply symmetry did not solve this. I have to check, but I might be possible to share a blend file where this is still occurring.
