Does a

CompositionLifecycleObserver

that enters a composition by being captured by a composable lambda get its callbacks invoked? E.g.

class MyActivity : AppCompatActivity() {
  private val myObserver: CompositionLifecycleObserver = object : …

  override fun onCreate() {
    setContent { MyApp(myObserver) }
  }

AFAIK the only way an observer can be “registered” is by being returned from

remember {}

.

Unfortunately it’s a little bit harder to define than that. If you are relying on it, use remember

also useful to know is that if an object that implements CLO is remembered in several places, it won't leave the composition until it leaves everywhere, including all of the cases of remembered parameters for restarting composable function calls.