[joe5150]

Does the Containerise extension do what you want? I've used it in the past for wildcard subdomains but not for ports.

https://addons.mozilla.org/en-US/firefox/addon/containerise/

[floralhangnail]

I have come across that one, but not having the "trusted" badge in the extension store has usually been a hard pass for me. I might reconsider.