Not sure why it would be so difficult since there was a working version of it before. I literally can't use this because I heavily rely on a password manager during my course of the day and copy/pasting my way around is not going to work. If one is not going to be made I will simply have to revert back to LastPass... unfortunately .
Pale Moon does not support WebExtensions, so unless a XUL-based extension is written, it will not work. It is becoming a very popular alt-browser for users of FFox... please consider writing one.