To be fair, here, Signal's whole original differentiating feature was cryptographically guaranteed forward secrecy (with non-interactive message delivery). Sign

To be fair, here, Signal's whole original differentiating feature was cryptographically guaranteed forward secrecy (with non-interactive message delivery). Signal therefore uses "ratcheting keys". If you let the current version of your keys, or even your chat history, get into a backup, you've ruined the main point. I do tend to agree that that kind of forward secrecy isn't actually important for very many people, and most of those people have other, bigger leaks to worry about. I don't use Signal myself. But it's still the big thing Signal was originally created to offer.