/**
  * Determine if we should load our admin pages class and if so, load it.
  *
  * Loads admin page class for all admin pages starting with `wpseo_`.
  */
 private function load_admin_page_class()
 {
     if ($this->on_wpseo_admin_page()) {
         // For backwards compatabilty, this still needs a global, for now...
         $GLOBALS['wpseo_admin_pages'] = new WPSEO_Admin_Pages();
         // Only register the yoast i18n when the page is a Yoast SEO page.
         if (WPSEO_Utils::is_yoast_seo_free_page(filter_input(INPUT_GET, 'page'))) {
             $this->register_i18n_promo_class();
         }
     }
 }