That's the sort of PoC that should be PGP encrypted to the Signal authors instead of publicly posted. Iran will have a field day with it being posted like this.

Except, of course, that posting public keys is too 1990s for him https://moxie.org/2015/02/24/gpg-and-me.html (which contains some good arguments but offers no solutions, so whatcha gonna do, post a phone number and trust the signal servers to give you the right public key? That's better than self-published public keys? For an anarchist? Is it smart to post phone numbers publicly anyway, see e.g. SS7?) Perhaps just ignore this paragraph, I'm just a confused person seeing mixed signals.