[XorNot]

Signal doesn't advertise a profile. It advertises a phone number - everything else is data you have locally. It will send a profile picture if you set one but that's it.

[itake]

Does it advertise your username? If I don't have the name of the contact, will Signal share my username or does it just say "this number in your list has joined signal, and here is their profile?"

[athrun]

My understanding is that your profile username is made visible if:

- the person is in your own contact list

- you create a conversation with them

- you accept a conversation from them

see: https://support.signal.org/hc/en-us/articles/360007459591

[toastercup]

Nice. Sounds like the same rules apply to profile pictures as well. That feels like a step in the right direction, but it still means that by having family/coworkers/college buddies/etc in your contacts, they can see your profile picture and username. I know this can be a sticking point for some. It would be great if Signal introduced finer-grained privacy controls so it could appeal to an even wider audience.

[itake]

You can download leaked phone numbers of millions of ppl and add them to your phone's address book (iOS limits contacts to 50k). I don't think this is very secure.

[athrun]

No, that would only allow them to see your name, but you still wouldn't see their names unless they add you.

[jraph]

You also see people's username when they are in the same group conversation as them (and they are not in your contact list).

That's what I observe by using Axolotl on the phone and Signal Desktop on the computer.