Any recommendations for glue to glue in my rear window to my 2000 ford mustang convertible?

There's a slight Detachment from the window and the top Any recommendations for glue to glue in my rear window to my 2000 ford mustang convertible

You missing some trim there? If so, that's likely what supposed to hold the upholstery up.
if not,
spray or brush on *auto* headliner glue. Do use *auto* glue. That will put up with temp differences the best.
avail at any auto parts store. Examples given in "source"