I'm hoping to add Fast Dial to the free software directory, https://directory.fsf.org/wiki/Main_Page. The problem is if I download the xpi, and open it up, I can't tell that it's free software because there is no information about what license it's under in the xpi. The easiest minimal thing to do is to add a file like README which says something like "all files are under x license." A few mins of work and it would be greatly appreciated. You can also add more comprehensive license notices if you want.