Constant PROBE_JS 

pub const PROBE_JS: &str = r#"(() => {
  const root = document.getElementById('root');
  const options = [...document.querySelectorAll('[role=button] img[alt^="Proceed to "]')]
    .map(i => i.getAttribute('alt').slice('Proceed to '.length));
  const captcha = [...document.querySelectorAll('iframe')].some(f =>
    /recaptcha\/(api2|enterprise)\/bframe/.test(f.src || '') && f.getBoundingClientRect().height > 100);
  return {
    host: location.host, path: location.pathname, ready: document.readyState,
    has_phone: !!document.getElementById('Phone'), options, captcha,
    text: ((root && root.innerText) || (document.body && document.body.innerText) || '').slice(0, 3000),
  };
})()"#;

Read-only probe of the login tab. Returns structure and fixed UI strings only; the CLI never prints text.