https://venngage.com/blog/wp-content/themes/venngage_v2/js/utmTracking.js

1/**
2 * utmTracking.js
3 *
4 * Tracks utms in header and save into cookie
5 */
6function saveUtmTagsToCookie() {
7    var utmValidTagsForAnalytics = ['utm_source','utm_medium','utm_campaign','utm_content','utm_term'];
8    var hostDomainParts = location.hostname.split('.');
9    var secondLevelDomain = hostDomainParts.length > 1 ? hostDomainParts.slice(-2).join('.') : hostDomainParts[0]; // 'es.venngage.com' -> 'venngage.com'
10    utmValidTagsForAnalytics.forEach(function(el) {
11        if (urlParam = getUrlParam(document.URL, el)) {
12            var utmVgCookieKey = 'vg_' + el; // e.x: vg_utm_campaign 
13            $.cookie(utmVgCookieKey, urlParam, {
14                path: '/',
15                domain: secondLevelDomain
16            });
17        }
18    });
19}
20
21saveUtmTagsToCookie();