Performed very poorly on test download of PBS video from youtube. The format in free version is very limited (if it ever completely downloads). It took extremely long to download file and never completed. The companion software was no better. I think this great extension is no longer that great. I would consider paying for software from many vendors that actually maintain good code and gui for this purpose or use one of many websites that do the job for you.

indispensabile

buena para seguir descargando y super sencillo

很棒的组件（is very good!!!)

最好用的一款软件，没有之一

Muy buena herramienta

ABSOLUTELY THE BEST VIDEO DOWNLOADER EVER. NO COMPETITION. DISABLE EVERYTHING ELSE.

One of the Best Video Downloading Plugin

It seems to give different options for the video quality each time you try to download the same thing.
When you just click on a download option it doesn't ask you where you want to save or tell you where it's saving it, you have to click on the right-arrow to the right to do that.
It doesn't show you the current download status or tell you when it's done.
The default filename for YouTube videos is apparently just "YouTube.webm" or whatever extension, so if you want to give it a decent name you have to type it out or copy it from the YouTube listing.
It has a ton of options for formats to convert the video to, including at least one audio format, but somehow it doesn't have any good, modern audio formats like m4a, ogg, opus or wma.
It requires you to download and install an external application for it to work, so you don't get the safety of just running an approved and contained FireFox addon, who knows what malware, spyware or adware is in it.
Just about the only good thing about this addon that it's actually able to download videos.
Actually, I take that back.. it only downloads successfully some of the time. Usually on YouTube I get an error similar to this:

Failed aggregating "Paul Anka - Let It Snow - YouTube"

D:\mp3\d:\mp3\christmas\youtube\Paul Anka - Let It Snow - YouTube-IDGEaS6vs8Y.mkv: Invalid argument

I haven't figured out a way around that. I'm lowering my rating from 3 to 2.

非常好用

Excelente herramienta de descargas, justo lo que estaba buscando.

llevo dias utilizandolo y creo que la mejor extension para descargar videos de paginas web , lo recomiendo esta buenisima.

Excelente para descargar los videos.

It's perfect, easy and strong. It's worth installing!

excellent functionality