code: function(id, url, entry, response) {
        return function wait() {
          try {
            (urlData[id].counter > 0) ? setTimeout(wait, WAIT_TIMEOUT) : response.json(entry);
          } catch (error) {
            console.log("   error -".red, "Error openning".yellow, url, error);
          }
        };
      }
docs: Send response only when iframe is loaded on all browsers (see "iframe-loaded" event on io section)