Sure it's not sufficient to formally prove security of the system e2e, but i'd guess it's sufficient for the average user. As for shipping a client with broken

Sure it's not sufficient to formally prove security of the system e2e, but i'd guess it's sufficient for the average user. As for shipping a client with broken encryption... Aren't people using Signal (like the person I originally responded to suggested) at risk of the same thing? Nobody's verifying checksums on every update except for people who aren't using WhatsApp for their comms anyway.