mod_http: Make RFC 7239 Forwarded opt-in for now to be safe Supporting both methods at the same time may open to spoofing attacks, whereby a client sends a Forwarded header that is not stripped by a reverse proxy, leading Prosody to use that instead of the X-Forwarded-* headers actually sent by the proxy. By only supporting one at a time, it can be configured to match what the proxy uses. Disabled by default since implementations are sparse and X-Forwarded-* are everywhere.