Navigation tab registration drift

An app with more than one form factor grows more than one navigation surface: a bottom bar for a compact window, a rail for a wide one, often a stylized bar behind a setting. Each builds its own:

val bottomNavScreens = listOfNotNull(
    BottomNavScreen.Home,
    BottomNavScreen.MixForYou.takeIf { showMixForYouTab },   // conditional
    BottomNavScreen.Analytics.takeIf { showAnalyticsTab },   // conditional
    BottomNavScreen.Library, BottomNavScreen.Search,
)

That literal appears once per surface, and the host picks between them on window width and on a user setting — so the surface you tested is the one you happened to be looking at.

The tab type is a sealed hierarchy whose ordinal is declared, not derived: