Mitch a écritMaybe pharan was right and I should just delete baking :/
Baking has absolutely nothing to do with your project.
Send your .spine file (with some blacked out source images if you must) to unity@esotericsoftware.com if you would.
Yeah I have no idea what it does to be honest haha, I just noticed the strange behavior of it toggling on.
I've send the e-mail, thanks for all the trouble again