EDIT 02/09/2019: Raised from 1 to 5 stars.
Tried this again on a Windows 10 and a Windows 7 PC. Worked "perfectly".
Well, the download button on the video itself is still not working. The quick download is tricky to get working. So maybe not "perfectly" but I love it again.
Also, it still remains true that the github page that this addon lists as its homepage has " 1 commit. 1 branch. 0 releases. 1 contributor" which does not sound right.
But for the moment, this is a killer addon for me. Makes downloading from youtube so quick and easy (once set up).
NOTE: for those who complain about permissions: It is a lot and that always concerns me. But these are all needed:
'Download files and read and modify the browser’s download history' is needed because it has a feature to auto-convert a video to a audio or .mp3 file. Also a feature to combine DASH separate audio and video files into 1. So it has to read the download history, find that file or those files and convert them. It also links the two history entries for the 2 file feature.
Also 'Exchange messages with programs other than Firefox' is need so that it can run ffmpeg to do these combines and extracts.
It also has a feature to use desktop notifications to report its activities. I happen to find that helpful, but some will not.
So I conclude that these are legit.
I loved this app. Today I got "signatureLocal: Signature could not be verified"
Yes and as other have said, the button in the video has gone. Have to click on the addon icon to get started. Also setting quick mp4 stopped working. Have to click on download panel then select mp4.
Those annoyance I could put up with. But now it just flat-out doesnt work.
Too bad. Was such a good app.
Its github page [https://github.com/feller-prj/extractor-project] today says " 1 commit. 1 branch. 0 releases. 1 contributor." That can't be true.
I fear it did change hands as another review mentioned. How can you tell? It's not in the releases listed on addons.mozzila.org?
Is it still working for anyone?
Developer: come here and save your addon (if that is truly your intention)