The extension works well in many regions. There are just a few videos which can't be downloaded due to restrictions.

Maybe you are using YouTube with the old layout. The button below the video only works with new YouTube layout. But there is always the download button in the Firefox toolbar available. With this button you can download videos as well. Please check and would be great if you could update your rating.

We use convert2mp3 for the conversion, but our workflow is much better than in their own add-on. We've released an update today so that parts of the website are blocked, which are loading popups. So feel free to update and enjoy with a clean workflow and layout. And would be great if you could update your rating.

Sure, the conversion has to be done with a webserver, MP3 conversion with a pure extension is impossible. If you think it's stupid, feel free to develop a better one.

No, the Download button is at the suitable place beside the video action buttons. The donate button is an optional thing.

Why just one star? It's in the description, that it's support for our add-ons.