{"type":"rich","version":"1.0","title":"paulmillr wrote","author_name":"paulmillr (npub10j…03kag)","author_url":"https://yabu.me/npub10jcnehsxwrjepupvh602pl83up0dh3wv3fqfwv062smygqvpeuwsk03kag","provider_name":"njump","provider_url":"https://yabu.me","html":"It's possible to deduce who messages whom (timing / correlation attack). All user contacts are uploaded to Signal servers (they say it's stored in SGX - which may be broken). Groups also store some data on Signal servers. And - most important - Signal relies on phone numbers."}