The download as MP3 is only with pro version available.

Worked only first time

nope, nix

Comme par hasard, après un ou deux downloads, un message bizarre avertit que ce n'est plus possible. Signaler un bug ? -> redirection vers une page (youtube-downloader.uservoice.com) où on est invité à donner une autorisation de cookies et... à faire un don. Je retire ce plugin tout de suite.

upgraded to pro version but cant seem to download the pro version

says you need to upgrade for 1080p and mp3 downloading, understandable given the circumstances. But the same goes for mp4 downloading as well in 720p. Waste of time this add-on

no download. Why?

It doesn't work on region blocked videos. And since I had installed this extension solely for this purpose...

DOES NOT DO ANYTHING what it promises!!!
Exept it offers you the ProVersion which is a payed service!!!
PLS. WAIT, THIS CAN TAKE TIME... is the only thing it does!
HANDS OFF!!! I definetly will not recommend it, I don't know, why Firefox officially recommends it!!!
I personally miss the '0 Star' button!

As SOON as I paid for the PRO version it STOPPED WORKING.

DOES NOT WORK, I USE SMALLEST FILE, DOES NOT DL, I GET FAILED MESSAGE IN DL ICON WINDOW OVER AND OVER NO MATTER WHAT SIZE I PIC

i don't work anymore !!

Wont download hi res videos with out a lot of other software or paid version. There are extensions that will allow you to down load video and sound as two separate files. Look for those.