Great guy for doing this all himself. Reviewing to support because I think what he is doing is awesome. This is it! The best youtube downloader in the Mozilla store! Super easy to use, no problems, I imagine very young children can easily be taught how to DL their favorite "Youtubers" in a few minutes. I think this is a great tool, excellent extension and it's functionality is far superior to other "add-on Downloaders" I have used in the past.