I have to say that this sounds very reasonable (and certainly a lot better than sending your plain text contacts). Does anyone know what kind of solution Signa

I have to say that this sounds very reasonable (and certainly a lot better than sending your plain text contacts). Does anyone know what kind of solution Signal is using nowadays? The linked article is not very recent and they might have changed their method in the meantime. I had a quick look at their source but was not successful in finding the relevant part for uploading the contacts.