3. Cryptographic primitives: Curve25519 / XSalsa20 256 / Poly1305 (downgraded for the absence of PQ encryption).
We added PQ encryption in March this year: https://simplex.chat/blog/20240314-simplex-chat-v5-6-quantum-resistance-signal-double-ratchet-algorithm.html
This is done in the same way as Apple describes as PQ3 here: https://security.apple.com/blog/imessage-pq3/
