Ligier JS19 extant?

I have read in the past that all of the Ligier JS19 chassis were converted to JS21s.

A JS19 appears in this video at the Conservatoire de la Monoplace at Magny Cours recorded 2 years ago. It appears 7 minutes into the video.
https://www.youtube.com/watch?v=Xg9PrzSl0n0

Does anyone know if this is a retro-conversion back into a JS19 or did this survive as a JS19?

Thanks