I’ll have to look into that 
I see it’s well done for audio; it’s almost exactly what I want. More precisely, I made a prototype somewhere, but I didn’t fully implement it. It’s more complicated there, of course. And maybe it’s more complicated here, too; there’s so much here. I might even be redoing it now; you already have it here
https://ankiweb.net/shared/info/1599302255