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.
return (
        <SuspenseList revealOrder="together" tail="collapsed">
          <Suspense fallback="Loading">Content</Suspense>
        </SuspenseList>
      );
    }
    ReactNoop.render(<Foo />);
    expect(() => Scheduler.unstable_flushAll()).toErrorDev([
      'Warning: <SuspenseList tail="collapsed" /> is only valid if ' +
        'revealOrder is "forwards" or "backwards". ' +
        'Did you mean to specify revealOrder="forwards"?' +
        '\n    in SuspenseList (at **)' +
        '\n    in Foo (at **)',
    ]);
  });
  it('renders one "collapsed" fallback even if CPU time elapsed', async () => {
    function Foo() {
      return (
        <SuspenseList revealOrder="forwards" tail="collapsed">
          <Suspense fallback={<Text text="Loading A" />}>
            <Text text="A" />
          </Suspense>
          <Suspense fallback={<Text text="Loading B" />}>
            <Text text="B" />