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.
case 'forward':
          case 'backward': {
            console.error(
              '"%s" is not a valid value for revealOrder on <SuspenseList />. ' +
                'React uses the -s suffix in the spelling. Use "%ss" instead.',
              revealOrder,
              revealOrder.toLowerCase(),
            );
            break;
          }
          default:
            console.error(
              '"%s" is not a supported revealOrder on <SuspenseList />. ' +
                'Did you mean "together", "forwards" or "backwards"?',
              revealOrder,
            );
            break;
        }
      } else {
        console.error(
          '%s is not a supported value for revealOrder on <SuspenseList />. ' +
            'Did you mean "together", "forwards" or "backwards"?',
          revealOrder,
        );
      }
    }
  }
}
function validateTailOptions(
  Mode: SuspenseListTailMode,