henningw left a comment (kamailio/kamailio#4168)
Its not a bug in Kamailio, but more a specification issue. A similar approach is done also at other places inside Kamailio. In my opinion this should be not changed isolated inside the path module without considering the impact and also check other places where this might be used in Kamailio. The relevant RFC part:
[5.2](https://datatracker.ietf.org/doc/html/rfc7118#section-5.2). SIP URI Transport Parameter
This document defines the value "ws" as the transport parameter value for a SIP URI [[RFC3986](https://datatracker.ietf.org/doc/html/rfc3986)] to be contacted using the SIP WebSocket subprotocol as transport.
The updated augmented BNF for this parameter is the following (the original BNF for this parameter can be found in [[RFC3261](https://datatracker.ietf.org/doc/html/rfc3261)]):
transport-param =/ "transport=" "ws"
As Olle stated, we are already in violation of the (proposed) RFC 5630, for similar reasons.
To emphasize what is already defined in [[RFC3261](https://datatracker.ietf.org/doc/html/rfc3261)], proxies MUST NOT use the "transport=tls" parameter.