Sandbox: https://codesandbox.io/s/cranky-kapitsa-op3jh

Repro: type "a" and then after a second "b"

Expected: Eventually you'll see "ab" in all fields. Pending "..." indicator goes away.

Actual: You'll keep seeing "a" in low pri field. Pending "..." indicator is stuck.
expect(root).toMatchRenderedOutput(
        <>
          <span hidden={true} prop="B" />
          <span prop="Loading..." />
        </>,
      );
      
      await resolveText('D');
      await ReactNoop.act(async () => {
        setText('D');
      });
      
      
      expect(Scheduler).toHaveYielded(['D']);
      expect(root).toMatchRenderedOutput(<span prop="D" />);
    },
  );
  it(
    'regression: primary fragment fiber is not always part of setState ' +
      'return path (another case)',
    async () => {
      
      
      
      const {useState} = React;
      const root = ReactNoop.createRoot();
      function Parent() {