Jetpack Compose version: CMP 1.8.0-dev1890

Material Library Version (M2, M3 or Both?): M3

Material Compose component used: androidx.compose.material3.TopAppBarState

Android Studio Build: #AI-242.23339.11.2422.12548333

Kotlin version: 2.1.0-Beta2

Steps to Reproduce or Code Sample to Reproduce:

It's obvious from looking at the line here, where heightOffsetLimit is a var and assigned a static value, and the violations here and here which re-assign the var.

This re-assignment means that anyone using heightOffsetLimit in a composable will not be notified when it gets updated. This manifests for me as a crash during scrolling because it's expecting a non-zero height, but the specifics are not important.

The state is marked @Stable here, so each publicly visible and mutable field needs to be snapshot aware.

As a workaround, if one does

val heightOffsetLimit by remember {
    derivedStateOf {
        // Force state read so this gets invalidated
        scrollBehavior.state.heightOffset
        scrollBehavior.state.heightOffsetLimit
    }
}

then it'll at least fix the crash on scroll, although you do miss out on the initial value and thus any placement relative to the app bar is broken until the user scrolls.

This was broken in https://android-review.googlesource.com/c/platform/frameworks/support/+/3123371

Stack trace (if applicable): N/A

Issue 377321472

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