window._trackJs = {
    onError: function(payload, error) {

        function itemExistInList(item, list) {
            for (var i = 0; i < list.length; i++) {
                if (item.indexOf(list[i]) > -1) {
                    return true;
                }
            }
            return false;
        }

        var ignorableErrors = [
            // General script error, not actionable
            "[object Event]",
            // General script error, not actionable
            "Script error.",
            // an error caused by DealPly (http://www.dealply.com/) chrome extension
            "DealPly",
            // this error is reported when a post request returns error, i.e. html body
            // the details provided in this case are completely useless, thus discarded
            "Unexpected token <"
        ];

        if (itemExistInList(payload.message, ignorableErrors)) {
            return false;
        }

        payload.network = payload.network.filter(function(item) {

            // ignore random errors from Intercom
            if (item.statusCode === 403 && payload.message.indexOf("intercom") > -1) {
                return false;
            }

            return true;
        });

        return true;
    }
};

window._trackJs = {
    onError: function(payload, error) {

        // ignore an error caused by DealPly (http://www.dealply.com/) chrome extension
        if (payload.message.indexOf("DealPly") > 0) {
            return false;
        }

        // this error is reported when a post request returns error, i.e. html body
        // the details provided in this case are completely useless, thus discarded
        if (payload.message.indexOf("Unexpected token <") > 0) {
            return false;
        }

        payload.network = payload.network.filter(function(item) {

            // ignore random errors from Intercom
            if (item.statusCode === 403 && payload.message.indexOf("intercom") > 0) {
                return false;
            }

            return true;
        });

        return true;
    }
};

--- 
+++ 
@@ -1,35 +1,21 @@
 window._trackJs = {
     onError: function(payload, error) {
 
-        function itemExistInList(item, list) {
-            for (var i = 0; i < list.length; i++) {
-                if (item.indexOf(list[i]) > -1) {
-                    return true;
-                }
-            }
+        // ignore an error caused by DealPly (http://www.dealply.com/) chrome extension
+        if (payload.message.indexOf("DealPly") > 0) {
             return false;
         }
 
-        var ignorableErrors = [
-            // General script error, not actionable
-            "[object Event]",
-            // General script error, not actionable
-            "Script error.",
-            // an error caused by DealPly (http://www.dealply.com/) chrome extension
-            "DealPly",
-            // this error is reported when a post request returns error, i.e. html body
-            // the details provided in this case are completely useless, thus discarded
-            "Unexpected token <"
-        ];
-
-        if (itemExistInList(payload.message, ignorableErrors)) {
+        // this error is reported when a post request returns error, i.e. html body
+        // the details provided in this case are completely useless, thus discarded
+        if (payload.message.indexOf("Unexpected token <") > 0) {
             return false;
         }
 
         payload.network = payload.network.filter(function(item) {
 
             // ignore random errors from Intercom
-            if (item.statusCode === 403 && payload.message.indexOf("intercom") > -1) {
+            if (item.statusCode === 403 && payload.message.indexOf("intercom") > 0) {
                 return false;
             }
 
Add improved logic to ignore errors in TrackJs
