Been using it for years. Works like a charm.

very nice add on

The creator of this extension is a very hard-working and dedicated person; he's kept it up for a long time despite YouTube constantly seeking ways of disabling it. Easy to use and generally reliable, though sometimes YouTube does catch up--briefly, never for long. I use it in conjunction with a standalone app that does some of what this doesn't, but the reverse is also true. Highly recommended.

Perfetto downloader, veloce e facile con buona scelta in quali formati

Does exactly what you need with no bullshit! AWESOME! THANKS! <3

Rápido e simples!

Very good!

very good extension

Awesome...Brilliant

good and helpful app

In short, easy to add to FireFox, VERY easy to use. Multiple resolutions to choose from. Love it.