Used to work well until a few months ago.
Fair enough, it is already the 2nd half of 2020.
Read their notice before berating and just ranting by rating this add-on irresponsibly.

Not working (as of a few days ago, maybe a week?). I suspect Youtube made website changes.

Sometimes it works, sometimes it does not. Has nothing to do with Firefox updates because it will or won't work on the same version.

Seems to be working without issue, however I only give this addon 3 out of 5 as it seems to be limited to downloading a maximum of 720p, even if the video is 1080p or higher. Even the settings shows a maximum of 720p.
I also have "video download helper" installed, which allows any quality to be downloaded, depending on the video source itself, but this addon only allows up to 720p, and I have no idea why. There doesn't seem to be any "pro" version or a version which you can pay for to get access to higher qualities.

this is awesome

I have FF76.0.1 and the latest version of the addon 1.0.9.86 and I still get the blank dropdown, i have removed completely and reinstalled and it stil wont work:O(

JUST TEST

Downloaded Facebook videos have no sound.

Works OK on YouTube, but No HD or 4K