> One could, however, add a second passphrase that is never sent to the server, and encrypt the data using that. Chrome provides this as a non-default option.
The average user doesn't have the expertise to know that they have to configure an additional "master password" to keep Google from mining their data for ads.
https://prod-cdn.sumo.mozilla.net/uploads/gallery/images/201...
I just got this morbid idea of Google mining storing passwords to recommend LastPass/1Password in ads based on your password strength.
The advantage here is twofold. - Your encryption key is derived from your single Firefox password, rather than having 2 passwords. - The ease of use of this system makes it possible to have e2e encryption by default rather than by opt-in.