answer:In regards to passwords Mozilla says Weave has “end-to-end encryption”, meaning even if someone were monitoring your internet connection, or looking at Mozilla’s servers, they could not read your passwords. Which leaves the files on your computer as the weak link. And I recently learned an easy fix for that. Settings -> Security -> Passwords -> Use a master password. With a master password, Firefox encrypts your data. Without the master password, it takes very little work for someone with access to your machine to read all the passwords. Somewhere I read that only NEW records get encrypted, so I synced my passwords to the cloud , deleted all the passwords, then re-synced with Xmarks to create a fresh new encrypted password database. I can’t tell you anything about protecting bookmarks & browser history, because I never looked into that because I don’t care about their security. P.S. XMarks is similar extension, which works with Firefox, IE, Chrome and Safari. There has been grumbling about Weave’s reliability, Xmarks is older and better tested.