Greasy Fork is available in English.
Lets you download reddit videos with sound. Supports multiple download providers
< Feedback on Simple Reddit Video Downloader (with sound) [Viddit/Rapidsave]
Sorry for not responding earlier, I've been busy.
It seems to be working fine for me on latest versions of both Firefox and Chrome. (Firefox 89.0.2 / Chrome 91.0.4472.124)
Do you have any other info you can give me? Are you sure you have the latest version? You could try re-installing the script, I guess.
If you open the console, do you see any relevant errors?
Also, a reminder that the script only adds the download button to Reddit hosted videos. Embedded 3rd party site content isn't supported. (You can usually download those yourself by just following the source links)
Still not working, at least on Chrome.