Greasy Fork is available in English.
A simple tool that adds YouTube-style buttons for multi-format downloading. Lighter than most download scripts.
< Feedback em Sleek YouTube Downloader
I unfortunately have not received the layout change on any of my devices yet, but I'll update as soon as I can.
Unfortunately it doesn't work anymore as of 27.01.23 after the layout update of youtube. (Possibly a css related problem).