@Joseph-TP Thanks, but unfortunately when I click this nothing comes up. Is there a way to populate this?

  @roblugg 

The "Connected Devices" list should be automatically populated once the IPv6 Internet connection is configured correctly and working.

  @woozle Thanks, but I am trying to set up this rule in order to bypass the CGNAT my ISP has and establish an IPv6 connection.

I was trying to work with this: https://www.reddit.com/r/PleX/comments/qf38iy/ipv6_plex_server_accessible_from_ipv6_networks/

but I can only find the IPv6 address which starts fd9c.

I also found this thread but can't understand a lot of what they are saying: https://www.reddit.com/r/hyperoptic/comments/xr9qmo/ipv6_with_own_router/

Basically just need to work out if there's a workaround to avoid paying my ISP for a static IP or whatever, or whether I have to just get one.

Thanks for your help, sorry if I'm being dense.