Not .ZIP resource pack unload if the game is restarted

I am editing a resource pack for myself, and to make edition easier I didn't pack it in a .zip folder. But it always unload when I stop and restart my game.

I am unsure if this only affects not .ZIP packs, but it only happened with this kind of folders for me.

here is the pack I was trying to load.

and here is a short video showing the problem.
https://youtu.be/leYbMSAd9MU