diff --git a/tarteaucitron.js b/tarteaucitron.js
index 698397a..0eb4bc4 100644
--- a/tarteaucitron.js
+++ b/tarteaucitron.js
@@ -17,7 +17,7 @@ var scripts = document.getElementsByTagName('script'),
 
 
 var tarteaucitron = {
-    "version": 20210422,
+    "version": 20210509,
     "cdn": cdn,
     "user": {},
     "lang": {},
@@ -517,13 +517,13 @@ var tarteaucitron = {
                         var tacRootAvailableEvent;
                         if(typeof(Event) === 'function') {
                             tacRootAvailableEvent = new Event("tac.root_available");
-                        }else{
+                        }else if (typeof(document.createEvent) === 'function'){
                             tacRootAvailableEvent = document.createEvent('Event');
                             tacRootAvailableEvent.initEvent("tac.root_available", true, true);
                         }
                         //end ie compatibility
 
-                        window.dispatchEvent(tacRootAvailableEvent);
+                        if (typeof(window.dispatchEvent) === 'function') {window.dispatchEvent(tacRootAvailableEvent);}
 
                         if (tarteaucitron.job !== undefined) {
                             tarteaucitron.job = tarteaucitron.cleanArray(tarteaucitron.job);
@@ -862,7 +862,7 @@ var tarteaucitron = {
             var send_event_item;
             if(typeof(Event) === 'function') {
                 send_event_item = new Event(event_key);
-            }else{
+            }else if (typeof(document.createEvent) === 'function'){
                 send_event_item = document.createEvent('Event');
                 send_event_item.initEvent(event_key, true, true);
             }
@@ -923,13 +923,13 @@ var tarteaucitron = {
         },
         "addClass": function (id, className) {
             "use strict";
-            if (document.getElementById(id) !== null) {
+            if (document.getElementById(id) !== null && document.getElementById(id).classList !== undefined) {
                 document.getElementById(id).classList.add(className);
             }
         },
         "removeClass": function (id, className) {
             "use strict";
-            if (document.getElementById(id) !== null) {
+            if (document.getElementById(id) !== null && document.getElementById(id).classList !== undefined) {
                 document.getElementById(id).classList.remove(className);
             }
         },
@@ -1028,11 +1028,11 @@ var tarteaucitron = {
             if (key !== "") {
 
             if (status === true) {
-                document.getElementById(key + 'Line').classList.add('tarteaucitronIsAllowed');
-                document.getElementById(key + 'Line').classList.remove('tarteaucitronIsDenied');
+                tarteaucitron.userInterface.addClass(key + 'Line', 'tarteaucitronIsAllowed');
+                tarteaucitron.userInterface.removeClass(key + 'Line', 'tarteaucitronIsDenied');
             } else if (status === false) {
-                document.getElementById(key + 'Line').classList.remove('tarteaucitronIsAllowed');
-                document.getElementById(key + 'Line').classList.add('tarteaucitronIsDenied');
+                tarteaucitron.userInterface.removeClass(key + 'Line', 'tarteaucitronIsAllowed');
+                tarteaucitron.userInterface.addClass(key + 'Line', 'tarteaucitronIsDenied');
             }
 
             // check if all services are allowed
@@ -1141,7 +1141,9 @@ var tarteaucitron = {
             tarteaucitron.userInterface.css('tarteaucitronCookiesListContainer', 'display', 'none');
 
             document.getElementById('tarteaucitronClosePanel').focus();
-            document.getElementsByTagName('body')[0].classList.add('tarteaucitron-modal-open');
+            if (document.getElementsByTagName('body')[0].classList !== undefined) {
+                document.getElementsByTagName('body')[0].classList.add('tarteaucitron-modal-open');
+            }
             tarteaucitron.userInterface.focusTrap();
             tarteaucitron.userInterface.jsSizing('main');
 
@@ -1149,13 +1151,13 @@ var tarteaucitron = {
             var tacOpenPanelEvent;
             if(typeof(Event) === 'function') {
                 tacOpenPanelEvent = new Event("tac.open_panel");
-            }else{
+            }else if (typeof(document.createEvent) === 'function'){
                 tacOpenPanelEvent = document.createEvent('Event');
                 tacOpenPanelEvent.initEvent("tac.open_panel", true, true);
             }
             //end ie compatibility
 
-            window.dispatchEvent(tacOpenPanelEvent);
+            if (typeof(window.dispatchEvent) === 'function') {window.dispatchEvent(tacOpenPanelEvent);}
         },
         "closePanel": function () {
             "use strict";
@@ -1182,19 +1184,21 @@ var tarteaucitron = {
             if (document.getElementById('tarteaucitronCloseAlert') !== null) {
                 document.getElementById('tarteaucitronCloseAlert').focus();
             }
-            document.getElementsByTagName('body')[0].classList.remove('tarteaucitron-modal-open');
+            if (document.getElementsByTagName('body')[0].classList !== undefined) {
+                document.getElementsByTagName('body')[0].classList.remove('tarteaucitron-modal-open');
+            }
 
             //ie compatibility
             var tacClosePanelEvent;
             if(typeof(Event) === 'function') {
                 tacClosePanelEvent = new Event("tac.close_panel");
-            }else{
+            }else if (typeof(document.createEvent) === 'function'){
                 tacClosePanelEvent = document.createEvent('Event');
                 tacClosePanelEvent.initEvent("tac.close_panel", true, true);
             }
             //end ie compatibility
 
-            window.dispatchEvent(tacClosePanelEvent);
+            if (typeof(window.dispatchEvent) === 'function') {window.dispatchEvent(tacClosePanelEvent);}
         },
         "focusTrap": function() {
             "use strict";
@@ -1249,7 +1253,7 @@ var tarteaucitron = {
             var tacOpenAlertEvent;
             if(typeof(Event) === 'function') {
                 tacOpenAlertEvent = new Event("tac.open_alert");
-            }else{
+            }else if (typeof(document.createEvent) === 'function'){
                 tacOpenAlertEvent = document.createEvent('Event');
                 tacOpenAlertEvent.initEvent("tac.open_alert", true, true);
             }
@@ -1259,7 +1263,7 @@ var tarteaucitron = {
                 document.getElementById('tarteaucitronAlertBig').focus();
             }
 
-            window.dispatchEvent(tacOpenAlertEvent);
+            if (typeof(window.dispatchEvent) === 'function') {window.dispatchEvent(tacOpenAlertEvent);}
         },
         "closeAlert": function () {
             "use strict";
@@ -1275,13 +1279,13 @@ var tarteaucitron = {
             var tacCloseAlertEvent;
             if(typeof(Event) === 'function') {
                 tacCloseAlertEvent = new Event("tac.close_alert");
-            }else{
+            }else if (typeof(document.createEvent) === 'function'){
                 tacCloseAlertEvent = document.createEvent('Event');
                 tacCloseAlertEvent.initEvent("tac.close_alert", true, true);
             }
             //end ie compatibility
 
-            window.dispatchEvent(tacCloseAlertEvent);
+            if (typeof(window.dispatchEvent) === 'function') {window.dispatchEvent(tacCloseAlertEvent);}
         },
         "toggleCookiesList": function () {
             "use strict";
diff --git a/tarteaucitron.services.js b/tarteaucitron.services.js
index 76e9337..fb2fe59 100644
--- a/tarteaucitron.services.js
+++ b/tarteaucitron.services.js
@@ -357,7 +357,7 @@ tarteaucitron.services.facebookpost = {
     "js": function () {
         "use strict";
         tarteaucitron.fallback(['tac_facebookpost'], function (x) {
-            var frame_title = tarteaucitron.fixSelfXSS(x.getAttribute("title") || 'Michel'),
+            var frame_title = tarteaucitron.fixSelfXSS(x.getAttribute("title") || 'Facebook iframe'),
                 width = x.getAttribute("width"),
                 height = x.getAttribute("height"),
                 url = x.getAttribute("data-url"),
@@ -1826,14 +1826,7 @@ tarteaucitron.services.gtag = {
                  * https://support.google.com/analytics/answer/7476333?hl=en
                  * https://developers.google.com/analytics/devguides/collection/gtagjs/cross-domain
                  */
-                gtag(
-                    'config',
-                    tarteaucitron.user.gtagUa,
-                    { 'anonymize_ip': true },
-                    {linker: {
-                        domains: tarteaucitron.user.gtagCrossdomain,
-                    }},
-                );
+                gtag('config',tarteaucitron.user.gtagUa,{ 'anonymize_ip': true },{linker: {domains: tarteaucitron.user.gtagCrossdomain,}});
             } else {
                 gtag('config', tarteaucitron.user.gtagUa, { 'anonymize_ip': true });
             }
@@ -3158,7 +3151,7 @@ tarteaucitron.services.verizondottag = {
         });
 
         tarteaucitron.addScript('https://s.yimg.com/wi/ytc.js', '', function () {
-            const items = window.dotq;
+            //const items = window.dotq;
             window.dotq = [];
             window.dotq.push = function (item) {
                 YAHOO.ywa.I13N.fireBeacon([item])