Water drops behind medium rear-view mirror – gasket panoramic roof?

Hello, had you ever had a water break in behind the rear mirror (XC 90), water dripped from the camera box except for middle jalousie: car was parked and it rained slightly but continuously. Front window had changed a few times I presented it to the workshop immediately: was artificially rained etc.: Demonstration effect – water didn’t penetrate an… no idea… before the sky was expanded, we wanted to wait for the next water break in again… Seals etc. are unfortunately not covered in warranty extension… Did I then look at the panoramic roof a few days later and find out that a piece of seal is missing on the passenger’s side behind (see photo). Workshop confirmed that this doesn’t look normal… Have you ever seen this before, there has been an action? How shrinks the sealing rubber – bird’s food is not so clean…?? Thank you in advance for your comments.