Add two download buttons to YouTube videos that allow you to download MP3 or Video without leaving the page with the option to choose the quality.
< Отзив за Simple YouTube MP3/VIDEO Buttons
Not to use with the old youtube, being that all are migrating to the new. It's in the script description.
For old youtube, I recommend this:
https://greasyfork.org/pt-BR/scripts/34613-download-mp3-video-for-youtube
Doesn't work on old Youtube
Title.