http://isdb4l77sjqoy2qq7ipum6x3at6hyn3jmxfx4zdhc72ufbmuq4ilwkqd.onion/blog/20240314-simplex-chat-v5-6-quantum-resistance-signal-double-ratchet-algorithm.html
Double ratchet algorithm is used in Signal, Cwtch and SimpleX Chat. But Signal app by allowing to use the same profile on multiple devices compromises the break-in recovery function of Signal algorithm, as explained in this paper .