Are there any Signal-based messaging applications that work on the desktop without having to tether an Android or IOS smartphone to it, and without having to use a phone number as identifier?
* open source, code on github
* e2e encryption (apparently derivative of Signal's Axolotl double ratchet)
* chat/voice/video, and group chats (all encrypted always)
* based in Switzerland, coding out of Berlin
* clients for iOS, Android, Mac, Windows, Linux, Web
* can sign up with phone number or email (or username? Not sure - I think you can find contacts via username, not sure you can sign up without email)
* reasonably responsive on twitter
* yada yada yada
Things like this: https://github.com/wireapp/wire-desktop/issues/80
Then there is the fact that the client acts as a browser that fetches information from the web automatically without blocking trackers itself. This is leaking metadata and actual data.
Riot is based on Matrix which is a decentralized protocol (you're not tied to one company), and it doesn't need your phone number.
If you want to argue that Telegram and Signal are comparable because Telegram has better UX and Signal better security and some people prefer UX to security, that's fine (I could not disagree more strongly, but at least it's a coherent argument). But don't pretend the thread isn't about security to make people believe that there's controversy about whether Signal is more secure. There is no controversy: Signal won the Levchin prize this year for the Signal Protocol and sets the standard for secure chat, and Telegram... well, let's just suffice it to say that it does not meet that standard.
I somehow doubt it.
EDIT: Oh, I was mistaken, apparently there is an option now. From Wikipedia:
On October 4, 2016, Facebook deployed end-to-end encryption as an optional feature for Facebook Messenger users. It is available in an optional mode called "Secret Conversations" and uses the Signal Protocol.