URL Mapping (Reverse proxying) domains, similarly to Discord activities

[twnlink]

I'd like it if there was an interface for adding a domain that Reddit reverse proxies, so I can connect to it over WebSocket or fetch it without contacting an admin to get my domain allowlisted.

This would effectively prevent the user's IP from being leaked to the service added, so there's less of a security concern. It could be locked behind a DNS TXT record or something if you'd want to verify the user owns the domain.

There is #61, but the overhead of an HTTP request per-event isn't feasible for highly real time applications.