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.
throw new Error('Expected to find the previous sibling.');
        }
      }
      prevSibling.sibling = newWorkInProgress;
    }
     
     
    const  = returnFiber.Effect;
    if ( !== null) {
      .nextEffect = current;
      returnFiber.Effect = current;
    } else {
      returnFiber.firstEffect = returnFiber.Effect = current;
    }
    current.nextEffect = null;
    current.effectTag = Deletion;
    newWorkInProgress.effectTag |= Placement;
     
    return newWorkInProgress;
  } else {
    throw new Error(
      'Did not expect this call in production. ' +
        'This is a bug in React. Please file an issue.',
    );
  }
}
function beginWork(
  current: Fiber | null,
  workInProgress: Fiber,
  renderExpirationTime: ExpirationTime,