I tried to search for that but for Firefox all three results I could immediately find were ages old so I am not sure they still work. Also, it’s important to w

I tried to search for that but for Firefox all three results I could immediately find were ages old so I am not sure they still work. Also, it’s important to write to disk very often for this purpose. And the encryption is important. And given that you are adding something that is in effect a keylogger and trusting it with all your inputs, I would not want just any random third party add on author to be in charge of that.