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.

Awesome video downloader. Will download almost any video from the internet. Would recommend to anyone.

The only reason for not using this superb add-on would be not knowing about it. OK, now you know!
And the only reason to criticize it is most likely lacking elementary computer skills. If you read this short review and trust it, you probably not among those.

It easy to use once you get familiar with its UI, has few issues and gets updated regularly as far as I noticed. It supports many sites, way more than described. Be advised, for best results, especially when you need to convert video/audio formats, use a support application, referred to as "Companion App", which can be downloaded separately.

This being said, it is by far one of the best add-ons I ever used, both on Firefox and on Chrome (or derived from it). I like it a lot and would recommend it as a must for all those willing to enjoy the streamed content off-line.

El mejor complemento, una vez que aprendes lo detalles de como usarlo en ciertas paginas,

下载的视频没有声音

This app is Amazing!... Best video downloader I've used without spending an arm and a leg.

ダウンロードできないところhttps://vjav.com/も簡単にできるといいのですがよろしくお願いします。

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!!

gutes addon

我经常使用它下载小视频

目前用過最好用的火狐影音下載套件，直覺又方便

使用感很好，支持，要是能够做到bilibili下载就更完美了

Очень выручает в обучении. Спасибо!

Top App , leicht zu bedienen , bin sehr Zufrieden

This extension used to be my favorite, and my go to for youtube, or other videos to download. Unfortunately the extension seems to have really decreased in quality.

By adding water marks, and downloading videos and music in very low quality it has really been frustraiting. Even if I set it to DL in highest, it forces it to download in a much lower quality version.

Really useful for HLS Streaming

I've been using Video DownloadHelper off and on over the years on various laptops and it's never disappointed. It's easy to use and self-explanatory. Love it. Would recommend it to anyone.

Отлично скачивает даже со сложных сайтов. Быстро и аккуратно в отдельную папочку.

Works on just about every website. Thanks very much VDH .

Программа очень выручила!