My theory is that the reason Signal was so reluctant to add slightly-less-secure-but-usable backups is that it is going to have some unified infrastructure for

My theory is that the reason Signal was so reluctant to add slightly-less-secure-but-usable backups is that it is going to have some unified infrastructure for crypto and messaging storage/backup. The backup usability weirdness makes way more sense in that context. I don't understand security/crypto stuff so much, but the new version of the server seems to use the same secret token for crypto transactions as it does for backup https://github.com/signalapp/Signal-Server/search?q=userAuthenticationTokenSharedSecret https://github.com/signalapp/Signal-Server/search?q=userAuth... , which offers some evidence that this be the case.