For those that are using Free Tube like I do google has scored another victory for themselves .... you can no longer download youtube videos by means of Free Tube .... youtube told them to disable that function and then reinforced it on their end so you couldn't download anything .... they even went so far as to making sure that even older versions of Free Tube would not be able to download ....
Google like M$ is tightening the noose ..... of course there are those that are going to say "their product .... their rules" and you are quite correct ..... after all it is not a matter of life or death ....
There are other ways to download youtube videos for Win using download managers but none that I am aware of in Zorin or Linux ....