`MenuItem.onNavDestinationSelected`と`android:menuCategory="secondary"`の関係

https://developer.android.com/reference/kotlin/androidx/navigation/ui/package-summary#(android.view.MenuItem).onNavDestinationSelected(androidx.navigation.NavController)

By default, the back stack will be popped back to the navigation graph's start destination. Menu items that have android:menuCategory="secondary" will not pop the back stack.

https://developer.android.com/jetpack/androidx/releases/navigation#1.0.0-alpha09 で経緯が分かる。

MenuItems with menuCategory="secondary" will no longer pop the back stack when used with NavigationUI methods. b/120104424

難しい！！！