Greasy Fork is available in English.
The fastest and best quality video and music (mp3) YouTube download plug-in from Onur YASAR!
< Feedback on Fastest Youtube Downloader! (Video or MP3)
The old version is no longer used by most people, so you can also switch to the new version.
Old youtube request
Could you create it so it also works in the old youtube layout? (You can switch to the old one by clicking on your profile pic and on the bottom there's a button to switch, and to go back just go to youtube com/new)