Why do I have to download a "Companion App" separately for the Video DownloadHelper and not get it from the Firefox Browser Addon Portal?

That seems dubious!

30% OF MY LIVE RECORDINGS FAIL OR ARE CORRUPTED. Now they're asking for donations. Please fix your program!!!

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。

I have no idea how this app works. It has been on my computer for a few years but I could never get it to work, although I kept trying intermittently. About a month ago it worked for the first time and now it's working all the time - but I still don't know how or why. Documentation might help.

bisher alles in Ordnung, seit kurzem wird ein QR-Code sehr groß auf das Video gelegt. Das ist sehr ärgerlich

Downloads Youtube videos as webm which is fine. Not so fine is the QR code watermark stamped in that needs a paid licence to remove. That info should be upfront, before download and install, not afterwards. A pity because I like their ethos, their transparency around donation problems they found using Paypal (tl;dr use stripe.com, not Paypal) and their support for Kiva donations. As they say, they need to eat too. Just let us know about QR codes first :)

使い易く満足しています。ありがとうございます。

Not bad