[urq] Sunroof liner glue?

[Quattro]

My new-to-me 83 Urq has a leather (look?) liner on the underside of the
sunroof which is starting to come loose at the edges.  It was clearly glued
at some time in the past, any ideas or btdt regarding gluing this piece back
up?  I have to imagine that whatever glue the makers used is now long gone,
hazardous, nla or worse.  I would also imagine that newer technology might
have come up with something better by now.

Ideas, suggestions, comments?

TIA!

>>>>>Bernie
83 Alpine White 900231