Repro: https://codesandbox.io/s/fast-water-4i4jb

Notice the flash. I'd expect `suspended` to be `true` during the high pri render.
Scheduler.unstable_yieldValue('Update did commit'),
      );
      expect(ReactNoop.flushNextYield()).toEqual([
        'Suspend! [Step: 2]',
        'Loading (1)',
        'Loading (2)',
        'Loading (3)',
        'Update did commit',
      ]);
      expect(ReactNoop).toMatchRenderedOutput(
        <>
          <span hidden={true} prop="Step: 1" />
          <span hidden={true} prop="Sibling" />
          <span prop="Loading (1)" />
          <span prop="Loading (2)" />
          <span prop="Loading (3)" />
        </>,
      );
      await advanceTimers(100);
      expect(Scheduler).toHaveYielded(['Promise resolved [Step: 2]']);
      expect(Scheduler).toFlushExpired(['Step: 2']);
      expect(ReactNoop).toMatchRenderedOutput(
        <>
          <span prop="Step: 2" />
          <span prop="Sibling" />
        </>,
      );
    });
    it('does not re-render siblings in loose mode', async () => {
      class TextWithLifecycle extends React.Component {