Ошибка "TypeError: undefined не является конструктором" в Python Webdriver ghostdriver.log

Question

Я запускаю WebDriver с PhantomJS:

def start_webdriver():
    try:
        driver = webdriver.PhantomJS('./phantomjs', desired_capabilities=dcap)
        return driver
    except WebDriverException, e:
        print "Unable to load profile, retrying"
        try:
            driver = webdriver.PhantomJS('./phantomjs')
            return driver
        except WebDriverException, e:
            print "Unable to load profile (again), aborting"
            return None

def webdriver_retry(driver, url):
    if url.startswith('//'):
        url = 'http:' + url
    driver.get(url)
    try:
        links = driver.find_elements_by_xpath(XPATH_MAPPING_HYPERLINKS['text'] % keyword)
        print links
    except InvalidSelectorException, e:
        print '{} - Selenium failed to perform XPath query to extract links. Killing Webdriver and moving to next URL'.format(url)
        print e.msg
        driver.quit()
        return
    hrefs = [link.get_attribute('href') for link in links]
    titles = [link.text for link in links]
    titles_and_links = zip(titles, links)
    print titles_and_links
    for title, link in titles_and_links:
        link.click()
        if keyword in driver.page_source:
            save_html(title, utf8_encode(driver.page_source))

где:

XPATH_MAPPING_HYPERLINKS = {'href': "//a[contains(translate(normalize-space(), 'ABCDEFGHIJKLMNOPQRSTUVWXYZ', 'abcdefghijklmnopqrstuvwxyz'), '%s')]/@href",}
keyword = 'manager'

Когда URL-адрес http://mcand.co.uk/our-people/current-vacancies/, извлечение XPath ничего не возвращает (как и должно быть, так как нет гиперссылок, содержащих текст 'manager'), но я вижу следующий в журнале ghostdriver:

[INFO  - 2016-02-15T20:03:22.587Z] GhostDriver - Main - running on port 53138
[INFO  - 2016-02-15T20:03:23.577Z] Session [2b080a10-d41f-11e5-8f67-6f1883fdd5c4] - page.settings - {"XSSAuditingEnabled":false,"javascriptCanCloseWindows":true,"javascriptCanOpenWindows":true,"javascriptEnabled":true,"loadImages":true,"localToRemoteUrlAccessEnabled":false,"userAgent":"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/38.0.2125.122 Safari/537.36","webSecurityEnabled":true}
[INFO  - 2016-02-15T20:03:23.577Z] Session [2b080a10-d41f-11e5-8f67-6f1883fdd5c4] - page.customHeaders:  - {}
[INFO  - 2016-02-15T20:03:23.577Z] Session [2b080a10-d41f-11e5-8f67-6f1883fdd5c4] - Session.negotiatedCapabilities - {"browserName":"phantomjs","version":"2.0.0","driverName":"ghostdriver","driverVersion":"1.2.0","platform":"mac-10.9 (Mavericks)-64bit","javascriptEnabled":true,"takesScreenshot":true,"handlesAlerts":false,"databaseEnabled":false,"locationContextEnabled":false,"applicationCacheEnabled":false,"browserConnectionEnabled":false,"cssSelectorsEnabled":true,"webStorageEnabled":false,"rotatable":false,"acceptSslCerts":false,"nativeEvents":true,"proxy":{"proxyType":"direct"},"phantomjs.page.settings.userAgent":"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/38.0.2125.122 Safari/537.36"}
[INFO  - 2016-02-15T20:03:23.577Z] SessionManagerReqHand - _postNewSessionCommand - New Session Created: 2b080a10-d41f-11e5-8f67-6f1883fdd5c4
[ERROR - 2016-02-15T20:03:59.224Z] Session [2b080a10-d41f-11e5-8f67-6f1883fdd5c4] - page.onError - msg: TypeError: undefined is not a constructor (evaluating '$(document)')

  :262 in error
[ERROR - 2016-02-15T20:03:59.225Z] Session [2b080a10-d41f-11e5-8f67-6f1883fdd5c4] - page.onError - stack:
  global code (http://mcand.co.uk/wp-content/themes/mcc/js/build/main.min.js:1)

  :262 in error
[ERROR - 2016-02-15T20:05:30.672Z] Session [2b080a10-d41f-11e5-8f67-6f1883fdd5c4] - page.onError - msg: TypeError: undefined is not a constructor (evaluating '$(document)')

  :262 in error
[ERROR - 2016-02-15T20:05:30.691Z] Session [2b080a10-d41f-11e5-8f67-6f1883fdd5c4] - page.onError - stack:
  global code (http://mcand.co.uk/wp-content/themes/mcc/js/build/main.min.js:1)

  :262 in error

Это проблема PhantomJS / ghostdriver? Или PhantomJS обнаружил ошибку в Javascript страницы? Если бы в тексте была ссылка с "менеджером", могла ли эта ошибка привести к тому, что PhantomJS неправильно выполнял XPath?

Будучи разработчиком Python, мои знания Javascript практически равны нулю.