Signal can track metadata: Where is the proof, where is the reference, where is anything of that? Moxie Marlinspike showed all his metadate in a talk of his. The only metadata there is to read is “lastSeen” and “accountCreated” which says basically nothing. No groups, no contacts, no everything. Bold assertion to say otherwise without any kind of proof.

You made me watch the video again and he does not make such a claim anywhere as far as I can tell.

But for what it is worth… there is a difference between storing metadata (which Signal probably doesn’t do, at least not on regular basis and only on a very limited scale) and being able to access metadata in real-time. The latter Signal can easily do and it can also easily be forced to do so with a gag-order by US authorities.