diff --git a/hosts/whitelist.txt b/hosts/whitelist.txt
index e0d502f..f2cfeeb 100755
--- a/hosts/whitelist.txt
+++ b/hosts/whitelist.txt
@@ -1,6 +1,9 @@
 ## This whitelist maintaince by @ookangzheng
 ## Attribution-NonCommercial 4.0 International (CC BY-NC-SA 4.0)
 
+# w3school cdn
+cs837.wac.edgecastcdn.net
+
 # Mailjet Short url for Email tracking 
 xqqyu.mjt.lu
 mjt.lu