@ted@gytis@rysiek@h3artbl33d@PINE64 signal's policy is irrelevant. the client is GPL. you can fork it and talk to signal servers just like you can fork chromium and talk to google servers.
@sneak@ted@gytis@h3artbl33d@PINE64 it is relevant, because if they wanted to, they could block your client. Signal is actively hostile to third-party client developers.
The right to fork is there, the right to use their servers is not.
@rysiek@ted@gytis@h3artbl33d@PINE64 they can't block it without making their official client nonfree, as a fork would be indistinguishable to the server.