Maybe it's me as I realize that my skills in this area may not be comprehensive enough to use this extension but I installed it with no problem. Then I tried it and it said I needed a companion app and gave me two options for that. I tried both options, even having to tweak my security settings to allow the .pkg file extension. Then it finally allowed me to choose the format/conversion except being a laymen there are so many options that seamed so similar like mp4 1mb vs mp4 2mb. So by one I tried the ones I recognized as to not overload/overburden my macbook or the server or whatever can get overloaded. None of the formats, not even one actually downloaded. I gave up, tried another similar extension. One click to download the extension, then one click to select the format then a third and final click to download the media. That's it! The other one worked. Maybe this extension is simply too sophisticated for my average/adequate skills. I'm assuming it's me but maybe this review will help developers think about us laymen when creating extensions in the future. Cheers!

made youtube videos unplayable

Allows you to download ONCE and then every video afterward will require you to install a third party application - even if you go to download the same video again, demonstrating that it's not just a certain type of video that requires the "companion application"

This screams malware.

The fact that you are forced to download an EXTRA APP in order to download HD videos is absurd.

Para descargart cualquier video pide instalar una "aplicación auxiliar" sin esa aplicación auxiliar no se puede descargar ni reporducir nada. Buscaré otro complemento que realmente sirva.

DO NOT USE. Absolute scam. Requires you to install their software (could be a virus), took a long time to download, and then had a massive QR code in the corner... the only way to remove the code is to pay them. Use another addon or just use the online video downloaders.

Simply does not work.
After installation I tried to download a video from YT (a free video; no music; no film; etc.). DownloadHelper asked me to install a companion file. After some research and re-thinking I pressed the button and there was -- nothing. An error message appeared (from github) that there was no such a repository.
So, that's it for me: I uninstalled this add-on.

下载的视频没有声音

Used to be great..now is terrible. The companion app constantly needs updating; however it never lets you know. The aggregating is a HUGE problem; it take hours to do this!! FIREFOX; please recommend another BETTER app!!

This extension is not working with latest Firefox version.

podre. precisa de um app adicional pra baixar videos. demora horrores pra um video de 50 minutos. Não recomendo. Procure um software mais confiável e eficiente, pois esse é inútil

QR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR codeQR code FU!!2!!!@!!

does not show up anywhere after installing it so no way to use it = CRAP

They put a QR in the corner of every videos that you download with it.

this barely works, and its supper suspicious. NOT Recommended; proceed with caution!!!

WARNING - Payment required for proper use. -- Otherwise: Not easy to use, the forum/support is not a nice place, and says it is downloading at a quality that it clearly upscales to after the effect.