frostStep property
Whether premium steps through premium without frost on its way to and
from standard. Defaults to false.
The iOS 27 frost (LiquidGlassSettings.frost) is the most expensive part of premium glass. With this on, the first step down from premium only switches the frost off, standing in a regular blur for it, and keeps the premium lens, rim and highlight; the next step goes to standard. Recovery takes the same two steps back. Glass without a frost looks the same in both premium steps.
Implementation
final bool frostStep;