What sort of glue or fixer will I need for this?

[linspins]

I need to fix a small piece of waterproof shower panel to plasterboard and then some metal trim, to finish off the outside of a shower unit. So it’s something waterproof fixing to something more absorbent. What sort of adhesive do you think I’ll need?
Photo shows the plasterboard bit, then the slice of shower panel and the silver trim.

multipanel adhesive, and read the instructions (or see video).

www.multipanel.co.uk/products/accessories/multipanel-seal/

other brands are available

Pigletjohn, you are a star! Thank you, that looks just right. 😁🤨
This was a job supposed to be done by the plumbers who fitted the shower room, and I’d been asking them ever since last March, to no avail. That’s what happens when you pay in full before a job is entirely finished. 🙁