In Preview, Fixed Position layers don't remain fix when they are near the bottom of the screen (?)
(During prototype preview)
As far as I can tell, this only happens to layers near the bottom of the screen.
The attached project shows a Snackbar, and a Status bar. During Preview, on screen 1, they have the correct offset from the bottom edge. (32px, and 0px, respectively). On screen 2 & 3, they should have the same offset, but instead they are floating some distance higher.