[MrMullen]

> Plus, getting a copy of all your contacts is and invasion of privacy for an app that is advocating for privacy and security.

You really need to do research into this before making this claim. The phone numbers are hashed (Or something like it) before being sent to the Signal servers.

[haffenloher]

Unfortunately, hashing provides no meaningful protection here. The preimage space (i.e. the set of all possible phone numbers) is just too small. See https://whispersystems.org/blog/contact-discovery/