Greasy Fork is available in English.
Adds a MP3 Download button next to the subscribe button, thanks to youtubeinmp3 for their simple download service (http://youtubeinmp3.com/api/). Based off magnus's youtube2mp3 code. Just used something different as it wont open another tab.
< Feedback on Youtube MP3 Download Button
Quality and Clip length
This script works.
Too bad the service this script are using, creates a lower conversion quality. And has a bottleneck, it can't convert longer clip than 110 minutes.
Other than that it's a great and fast script. Good Work.
For those who want higher quality and convert longer clips. Try mine: https://greasyfork.org/scripts/1931-youtube2mp3