diff --git a/packages/browser-sync/lib/server/proxy-utils.js b/packages/browser-sync/lib/server/proxy-utils.js
index 81b8827d8..ec03a8997 100644
--- a/packages/browser-sync/lib/server/proxy-utils.js
+++ b/packages/browser-sync/lib/server/proxy-utils.js
@@ -142,7 +142,7 @@ function rewriteCookies(rawCookie) {
 
     var pairs = Object.keys(objCookie)
         .filter(function(item) {
-            return item !== "domain";
+            return item.toLowerCase() !== "domain";
         })
         .map(function(key) {
             return key + "=" + objCookie[key];