Clear field focus when keyboard is hidden

Question

How to listen for a system button to hide the keyboard in order to remove focus from the input field? Like, for example, in Google Keep.

@Composable
fun PrerequisiteAddScreen() {
    var value by remember { mutableStateOf("") }
    val focusManager = LocalFocusManager.current

    SelectionContainer {
        TextField(
            value = value,
            onValueChange = { value = it },
            placeholder = { Text("Enter text") },
            keyboardOptions = KeyboardOptions.Default.copy(imeAction = ImeAction.Default, keyboardType = KeyboardType.Text)
        )
    }

    if (...) {
        focusManager.clearFocus()
    }
}