VideoDownloadHelper is, conceptually, a great add-on for Firefox. I feel, however, that the product (sadly) still has some further thought needing to be put behind it to turn it into the kind of download helper that it could, and, should be.
When it works, it usually works well. Sometimes, however, for no reason, it does not work.
My biggest gripe, actually, is that the functionality is very esoteric / arcane in that the developer, even with the right intentions, has not "translated" the functionality into something that is easy to use / intuitive / friendly. Frankly, I find this a bit odd -- how does one not find out from potential users what their issues are, etc.?
There are still quite a few aspects to this add-on that, frankly, I have no clue about, and, can't make sense of. And, by the by, I'm an above-average tech user, so, I SHOULD be able to follow the logic easily.
So, so ... not meaning to be harsh. This product, 70% of the time, is very useful. I urge the developer, though, to elevate this app to a "100-percenter" which would be amazing, and, which would become a major money-spinner for said developer. Right now, it's a half-job, sadly, though, still worth going through the motions to use it, as, often, it does work well. I think (maybe?) a first step for the dev. should be to make usage of the add-on a LOT clearer and easier. I mean, this is overly obvious. From there, some good tweaking / researching users would / could make this a fine add-on.
My humble 5c worth...

このアドオンなくして私のfirefoxライフは成り立ちません。本当にありがたいです。

NB Plus

niu b，very good！！

I love it, it does what i need it to do.. YMMV

Unclear, problematic, can't even download single youtube video. Even if it accidentally starts it is so slow, 1 minute low quality videos can't be slowly downloaded as webm like that. Looks like a joke. Never had luck with this extension really.

This used to be great, now its broken and states it needs to download unknown software to work.

No longer works with YouTube or Twitter September 2021.

Très satisfait de ce module :)

Meist gute bis sehr gute Arbeit. Doch bei manchen Plattformen funktioniert es nicht oder ungenügend. Hat sich leider nicht geändert.

No longer works with youtube and twitter August 2021.

Excelente

As an online student I love this app ... I download course videos to watch later when I am offline. I find the occasional video I can't download - but 98% of the time it is golden!

Very disappointing, It does less and less now. I used to love this but it seems to only do older videos. I have not been able to use on many platforms now. I think its out of date too quick.27/08/21.

Muy buena la extensión

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