https://codesandbox.io/s/upbeat-frost-3tt25

1. Press Suspend, see "Loading..."
2. Wait five seconds, you'll see "Happy birthday" at some point 
3. You won't see it again no matter how long you wait

Expected: you'll see it every five seconds.
}
      const fallbackChildFragment = createFiberFromFragment(
        nextFallbackChildren,
        mode,
        renderExpirationTime,
        null,
      );
      fallbackChildFragment.return = workInProgress;
      primaryChildFragment.sibling = fallbackChildFragment;
       
       
      workInProgress.memoizedState = SUSPENDED_MARKER;
      workInProgress.child = primaryChildFragment;
      return fallbackChildFragment;
    } else {
       
      const nextPrimaryChildren = nextProps.children;
      workInProgress.memoizedState = null;
      return (workInProgress.child = mountChildFibers(
        workInProgress,
        null,
        nextPrimaryChildren,
        renderExpirationTime,
      ));
    }
  } else {
     
     
    const prevState: null | SuspenseState = current.memoizedState;
    if (prevState !== null) {