how to solve RTCIceServer.url is deprecated! Use urls instead ?

Answer 1

(I'm answering you subject, since the rest of your question seemed unrelated).

The Firefox web console warning "RTCIceServer.url is deprecated! Use urls instead" refers to your RTCPeerConnection configuration.

Locate code similar to this:

var pc = new RTCPeerConnection({ iceServers: [{ url: 'stun:foo.com:1234' }] });

and rename it to:

var pc = new RTCPeerConnection({ iceServers: [{ urls: 'stun:foo.com:1234' }] });
                                                   ^

The name changed, because each ice server may in fact have multiple ways (URLs) in which it can be located, depending on network topology.