diff --git a/core/scripts/webpanel/templates/settings.html b/core/scripts/webpanel/templates/settings.html
index 425058f..9ae1de8 100644
--- a/core/scripts/webpanel/templates/settings.html
+++ b/core/scripts/webpanel/templates/settings.html
@@ -288,7 +288,8 @@
         // Validation functions
         function isValidDomain(domain) {
             if (!domain) return false;
-            return !domain.startsWith("http://") && !domain.startsWith("https://");
+            const lowerDomain = domain.toLowerCase();
+            return !lowerDomain.startsWith("http://") && !lowerDomain.startsWith("https://");
         }
 
         function isValidPort(port) {