code: function handleConfigChange() {
    var newRecaptchaValue = document.querySelector(
        'input[name="recaptcha"]:checked').value;
    var newEmailSignInMethodValue = document.querySelector(
        'input[name="emailSignInMethod"]:checked').value;
    location.replace(
        location.pathname + '#recaptcha=' + newRecaptchaValue +
        '&emailSignInMethod=' + newEmailSignInMethodValue);
  
    // Reset the inline widget so the config changes are reflected.
    ui.reset();
    ui.start('#firebaseui-container', getUiConfig());
  }
docs: Handles when the user changes the reCAPTCHA or email signInMethod config.