Doesn't download mp3 at all.

Doing a great job! - If youtube makes changes, Add-On will be fixed in shortest time!

tried several downloader extensions, none of them any good. give details later.

Consistently worked through all youtube updates for years: can't live without it!
The ONLY one that works flawlessly

The add-on does what it claims to do. No problems there. Whenever youtube makes changes to prevent downloaders from working, this add-on stops working for a while until the author modifies it. During that time, any other youtube downloader I've tried also has stopped working. This add-on begins working before the others do. That's why I stick with it.

Fast and efficient! Love the tabs that show up right under the video. This add-on is the best!

This used to work, then the author locked videos behind a pay wall. There is some paper thin excuse about how YouTube change the algorithm (True) so this can no longer provide downloads without infrastructure (false!) I don't know the actual code base, so take this with a grain of salt. However, as someone that understands video and audio encoding and containerization, this seems like bulls$h!t. There is no conceivable thing that could have changed that would make re-containerizing separate video/audio streams problematic without server infrastructure. mkv is an open standard, and there exists plenty of methods, including the browser, for repacking it on the client side. This extension is the authors ONLY project, hasn't been around for long, and doesn't do anything too novel. I suspect this was always just a coding cash grab, and we are just caught in the "capitalize" phase. Jump ship, something else will take it's place.

NO sirve.
Para usarlo hay que suscribirse al servicio "PRO" que cuesta caro.

This is an outstanding FF AddOn!
If you always wanted to access HD quality video on YouTube offline this is for you. Simply the best I've found, and the creator, Dishita provides timely updates too!
It's a steal at a $10 donation, but I like to watch offline in HD so I bought the Pro version.