Google Play Services and your contacts are completely different things. I'm confused on what information you think is being sent. As far as I'm aware, all FCM d

Google Play Services and your contacts are completely different things. I'm confused on what information you think is being sent. As far as I'm aware, all FCM does is provide a push that tells the app to check in with Signal's server. No contact information is in play. Signal also released a WebRTC version that doesn't depend on Google Play Services if that floats your boat.