They usually just get loose on the butyl adhesive contact. Not likely to break unless someone has been there and intentionally done something wrong. Like said could be just resealed by warming up the butyl and pressing them back on firmly. Actually this can be done as a quick fix by just pulling the lower part of the door card and doing it from between, because the culprit is on the lower edge of the barrier.

Yeah they aren't cheap at $72 each... Check ebay and there was a pair of new Genuine front door vapor barriers. for $130

Part of the issue is the E53 vapor barriers are much thinner /more fragile than the E39 vapor barriers. I chalk that up to a US supplier and/or cost cutting..

The E53 vapor barriers tear if you look at them wrong..

You can try a junkyard, but you are not likely to find them in one piece.

Ha! No kidding. The window mechanism engineering is often enough for me to consider it.

OK, I had not considered eBay... and yeah nearly every junkyard E53 has had the door cards pulled and the barriers ripped off to get at the door guts.

Came back on Weds, still a little damp back there, but it was closed up for two weeks and cold here so no oppty to dry it out.

Gonna throw some DampRid in it and wait for spring I guess, or at least some warmer days. I still think there's a sunroof drain issue tho since the cleaning wire did not make it into the sunroof tray from the left rear drain in the hatch. Gonna pull the A-pillar covers too and check for kinks/clogs, along with the rear door cards to check the barriers. I think FCP is the cheapest source for those, everything on ebay is a lot more or isn't until you add $25 for shipping from Latvia or wherever.

Paint Protection Film to seal leaking sunroof
 

Why don't you just seal the sunroof with Paint Protection Film? That way you can eliminate the leakage, once and for all, assuming that that's where the water comes from. And, you don't use the sunroof anyway.

I sealed mine (not a pano roof), using 6" wide clear PPF, back in October '21, https://xoutpost.com/1211529-post23.html and it's still good, despite the harsh Texas sun and wild weather. I have replacement film on hand to use if it ever starts lifting, peeling, or cracking (I check it every week, at least. I also made a roof rack out of close-spaced wire shelves, to keep tree debris and hail from hitting the sunroof and protective film. Of course, I removed the fuse to assure that the sunroof couldn't move, too.

I used XPEL Clear Paint Protection Film Rolls, 6" x 84" and 6"x 48", and have a 6"x84" roll ($23.91 @ Amazon) and a 6"x 60" roll ($19.60 @ Amazon) in my spare parts kit for future use.

It may come to that. Right now it's sealed up with Gorilla tape, which may have been a bad idea, but it's all I had at the time.

For now it's in covered parking; I've got a bigger problem that just started to deal with...