Liquid glass is poured over a bath of liquid tin where it floats on top, gradually cooling until it can be lifted off, annealed to prevent cracking, cut and packaged.
Also, this all has to be done without oxygen, because tin dioxide will stick to glass
I could never get a reply to post before, but I had fun watching videos of those machines! I liked the one with 30 or so little yellow bobbins dancing around, and the giant metal monster one was intimidating at first but the braid was really satisfying