I think that the glass element should go into the liquids tab, because technically, glass is actually a really slow moving liquid. please contemplate. ALSO--- think about how old glass panes are thinner at the top than at the bottom.
If anything, i think that this property of glass should make it into TPT for everyone to see.
Making glass slowly flow will break a lot of saves.
No. Glass is a solid because it doesn't move in TPT, right?
That difference in thickness is NOT because it has flowed over time. It occurs because very old glass panes were hand-made. In modern times, we have machines that create glass panes perfectly, and these do not change shape over time.