This add-on actually can *not* save videos. In order to save a video, it asks for downloading a 'companion' app, which is an executable that has to be installed separately and hence the browser security restrictions do not apply to it - it can do virtually anything.
This is highly suspicious, because external applications are not necessary in order to save files. I removed it and installed a different video downloader add-on which can save files just fine without 'companion' executables.
Another suspicious thing is that this addon requires some permissions which are not needed for the functionality it provides.

I want an addon that does exactly one thing, download videos. This addon used to do this, but now they have started to run videos through some kind of converter (= slow) and leaving a big watermark on the video, asking for money to remove it. Completely useless, uninstalled.

Works really well in theory, but as others have said before, it puts a huge watermark on the downloaded video, then asks you to buy a "premium" version without that anti-feature.
The add-on does not tell you that beforehand, not even in the description! Downloading a video can take a long time so it is deliberately wasting your time just to increase the chances of you paying for it. I call this misleading and a shady business practice.

Why does it need all these autorisations: Access to your data for ALL websites, exchange messages with OTHER programs than Firefox, consult and modify the history of downloads, access Firefox activity while browsing Internet.

this app asks for way too many access permissions. Check carefully before accepting them.

also places a huge, intrusive QR code "watermark" on top of the content

Не работает!
Просит скачать дополнительные приложения!
После скачивания дополнительных приложений, конвертирует видео с водяным знаком!!!
Для возможности получить видео без ВСТРОЕННОЙ РЕКЛАМЫ требует заплатить 28$ !!!!!!!!!!!!

ВЫ ТАМ ЕБАНУЛИСЬ В КРАЙ ????????????!!!!!!!!

I previously gave this ad-on high marks.
Now it unfortunately no longer works with Firefox as it did before.
There may be ways to get it to function, but I don't have the time or interest.
If making this software comply with Firefox requirements isn't worth it for the developer I simply have to agree and move on to the next download option.
It was great while it lasted.

vereist nu een extra app om video's te downloaden. en deze is nu betalend!!

Leider ist es das einzige Tool, das ich gefunden habe mit dem ich Videos ohne Konvertierung direkt herunterladen kann. ClipConverter hat mittlerweile zuviele Sperren und Popups drin.
Nun aber zum VDH das mit einem neuen Win 10 Rechner und dem aktuellen Firefox genutzt wird:
1. Es frisst sehr viele Ressourcen so dass alle anderen Downloads abgebrochen werden.
2. Mehrere Downloads gleichzeitig stellen ein weiteres Problem dar > zuviele Abbrüche.
3. Das Schlimmste ist die Meldung dass der Download erfolgreich beendet wurde. Leider fehlt am Zeitbalken eine Info wie lange der Originalfilm läuft. Ob der heruntergeladene Film wirklich zu 100% vollständig ist kann man nur prüfen wenn man den Film öffnet und die Spielzeit vergleicht.
4. Ich kann den Downloadort nicht wirklich beeinflussen. Denn zuerst wird anscheinend auf C geschrieben und nach Abschluss in den Soll-Ordner kopiert oder verschoben.
Sobald ich ein besseres Tool gefunden habe fliegt dieses wieder von meinem Rechner.

I downloaded a big video, waited for many hours for it to convert and AFTER the conversion it tells it'll have a watermark. It could warn me when asked to intall the companion app, but no! After 9 f... hours of wait, it give me an enormous watermark in the screen...

una volta era semplice scaricare video con questa estensione, adesso lavora un sacco, mi chiede dove salvare, poi lavora per un sacco di tempo in una fase "aggregazione" e non salva nulla

This addon was great, until it started watermarking every video, 'converted' or not and requiring a license to be purchased to download without the watermark.

This addon is now useless and should be avoided. Removed from all my machines.

Scam. Forces you to pay for registration or puts a giant watermark ruining video.

Waste of time.

Cuts videos short

Places a huge, intrusive QR code "watermark" on top of converted videos. Avoid!

I hate when the developer trying to FORCE me into buying. Removed.

При скачке видео требует установить дополнительное платное приложение партнера.

it needs to install companion app

Völlig überfrachtete, unverständliche Konfiguration. Versucht ständig die Installation der Begleitanwendung zu erzwingen. Alles läuft auf den Verkauf von Lizenzen hinaus. Downloads werden sonstwo gespeichert. Es ist mir nicht gelungen, die App dazu zu bringen nach dem Ziel zu fragen.

This is the shadiest addon I've ever seen. I can't believe it hasn't been removed yet. After installing and trying to capture a video it takes you to a page asking to install a separate executable, and then after installing the executable it takes you to a page requiring a 30 dollar license fee.

Для того что бы приложение работало надо еще скачать какуе то программу! ЗАЧЕМ мне еще что то качать ?! Также ничего толком не качается с youtube