I love PasswordMaker. What a fantastic extension.
I've been having problem since 0.9. (Currently using 0.9.1.) I used to select Populate with PasswordMaker on a password field, and the generated password would automatically appear. It still does this, but it always populates with an incorrect password. Yet, I can go to the PasswordMaker dialog and click "Copy Generated Password to Clipboard", paste the password in, and it works fine.
I'm using Firefox 1.5b2. Not sure if that is a problem. Is there an option to check?