ga(function (tracker) {
// Gets the client ID of the default tracker.
var clientId = tracker.get('clientId');
// Gets the Checkfront iframe.
var checkfrontIframe = document.getElementById('CHECKFRONT_WIDGET_01').getElementsByTagName('iframe')[0];
// Sends the client ID to the window inside the destination frame, once it's loaded.
checkfrontIframe.addEventListener("load", function () {
this.contentWindow.postMessage(clientId, 'https://thingstodoglobal.checkfront.com');
});
});
