It's a good extension that functions much better than other YouTube downloaders, but it has ceased working on Waterfox (which began using its own registry keys in version 2020.6). It's many months later and I'd say speedy updates are not a strength.

Worked great right out of the box. The "quick download" feature is fast & simple, good stuff.

Fonctionne parfaitement bien à ceci près qu'il sépare l'audio de la vidéo (je m'en fous pour mon usage). Interface très sobre, intégrée dans le lecteur Youtube.

Juste avant j'essayais de faire fonctionner videodownloadhelper (oui cette antiquité) mais c'est devenu un vrai veau : obligé de télécharger une autre appli (à installer) pour que le téléchargement fonctionne... je pite pas : je vais ailleurs.

Works great for downloads but it stopped joining audio and video together a long time ago and it hasn't been fixed since. Doesn't seem to matter what version of ffmpeg I use.

GooooD

Firefox 48 and 52 - does not work
Mobile Youtube - error

Do you want to download some garbage to your computer for this app works?

Works as advertised, but the MP3 converter function is garbage. all the audio I was getting after conversion was peaking and full of static. Ran it through ffmpeg locally and it sounds fine.

用了这么多唯一可以下YouTube视频的插件，嘿嘿~

You can download the video and also convert it to audio only.