From the bug tracker https://bugzilla.mozilla.org/show_bug.cgi?id=956906#c100 https://bugzilla.mozilla.org/show_bug.cgi?id=956906#c100 Summary of the change, s

From the bug tracker https://bugzilla.mozilla.org/show_bug.cgi?id=956906#c100 https://bugzilla.mozilla.org/show_bug.cgi?id=956906#c100 Summary of the change, so people don't have to wade through a long discussion: - This change makes it so that `autocomplete=off` does not stop the Password Manager from working. Normal form autofill can be disabled as usual. - The password manager *always* prompts if it wants to save a password. Passwords are not saved without permission from the user. - We are the third browser to implement this change, after IE and Chrome. - This can be undone locally by flipping the `signon.storeWhenAutocompleteOff` pref (from about:config) off. - The rationale behind this change was the widespread abuse of the `autocomplete` attribute to prevent password saving where no prevention is required. This change gives users full control over password saving, without compromising on security (again, the user is always prompted).