Your comments

Once again: downloading from the link worked well untill a week ago !! So you did support the mp3 recordings there !

It worked fine only a week ago or so from this site with savefrom !!!

You said the add-on is out-dated. download of mp3 dit not work anymore, so I tried to update for Firefox. Did not work. today I removed the add-on , closed Firefox ( I always have the latest version, now 61.0.1), add added again. No result, cannot download files. What is going on???

Windows 10 Home 32 bit, Firefox 61.0.1 

This is the site:

Earlier it worked fine downloading from this site.