Does this affect the end to end encryption mechanism of WebRTC (at least for Internet users)?
In other words, can Telefonica make it easy to spy on all Firefox Hello talks, or only on the browser-to-phone ones? (which is to be expected, I guess).
From my understanding of the WebRTC spec, as long as your TURN/STUN server is trusted (which it is, the CA and relay are both run by Mozilla) it doesn't matter if the network is untrustworthy.
Presumably offering routing servers and transit. Plus Telefonica bought TokBox[1], whose tech powers the backend
[1] https://tokbox.com/