This is a great add-on. I have used it for years to extract videos for my prison ministry. However, like Devilshaker, it has stopped working for me. I also uninstalled and then reinstalled the add-on. This worked that last time I encountered the cannot detect url_encoded_fmt_stream_map... but not this time. Perhaps the developer has not yet fixed the current version for this occurance of the problem. I hope it gets fixed soon.

not bad seems to get the job done.

26 April 2020: since a few days (21 april update) the programm gives me -cannot detect url_encoded_fmt_stream_map or adaptive fmts.
I've deleted the add-on and re-installed it, but the problem is still here.

muy util para descargar videos y audios de youtube exelente

fast download,just perfect!

nice addon!!

First downloader to actually work & let me download YT videos as MP3s through a built-in converter.

UPDATE! Now it still has errors everytime I try & merge audio/video, & when it succeeds, the file is only 22 seconds long! WTF is the point in THAT?! SMDH! Fix this shit already, please, would you?

It won't combine both the video & audio for vids DL'd via YT, & I have the latest FFMpeg installed too! & it is all config'd properly but yet will NOT combine both when DL'ing, & when I try & combine them afterwards in Media Muxer & Converter, it gives an error msg everytime I try & add the audio file to the video combiner. This addon USED to work just fine, flawlessly, even. Now it won't do what it's intended to do! & I recently formatted my SSD, & reinstalled EVERYTHING, so, very doubtful of any corruption. & I have a very good Internet Security suite installed & config'd properly too. So, WTF is the problem?

Used to work fine. Now it fails and says "are you sure the native client is installed ?" Duh, yeah !
The native client passes the connection test. All the paths are correct. And like I said, it used to work (yesterday). I even tried removing it and re-adding it. No dice. Maybe Youtube changed something ?

Looking at the browser console, it says:-

null ExtensionCommon.jsm:740

Unchecked lastError value: Error: An unexpected error occurred ffmpeg.js:14

This works. No need to look elsewhere, fellow collectors. I'm not a shill, it's legit. I'm talking about YouTube Video and Audio Downloader (WebEx). I added that because I see a lot of reviews that say "good add-on" and could be reviewing anything.

Two other add-ons and an application to install just to download a video or convert one? Streamline it or warn people. Do better. Uninstalled.