Maybe I missed it but I don't see this case in DOM fixtures:

https://github.com/facebook/react/pull/7359#discussion_r77518170

Seems important because it's easy to accidentally gloss over it if we stop syncing attributes and have to edit a bunch of jsdom tests.
const query = parse(window.location.search);
    query.production = event.target.checked;
    if (!query.production) {
      delete query.production;
    }
    window.location.search = stringify(query);
  }
  handleFixtureChange(event) {
    window.location.pathname = event.target.value;
  }
  render() {
    return (
      <header className="header">
        <div className="header__inner">
          <span className="header__logo">
            <img
              src={process.env.PUBLIC_URL + '/react-logo.svg'}
              alt="React"
              width="20"
              height="20"
            />
            <a href="/">
              DOM Test Fixtures (v
              {React.version})