diff --git a/root/defaults/ssl.conf b/root/defaults/ssl.conf
index 89099aa..ca6a007 100644
--- a/root/defaults/ssl.conf
+++ b/root/defaults/ssl.conf
@@ -40,7 +40,7 @@ ssl_early_data on;
 
 # Optional additional headers
 #add_header Cache-Control "no-transform" always;
-#add_header Content-Security-Policy "upgrade-insecure-requests";
+#add_header Content-Security-Policy "upgrade-insecure-requests; frame-ancestors 'self'";
 #add_header Referrer-Policy "same-origin" always;
 #add_header X-Content-Type-Options "nosniff" always;
 #add_header X-Frame-Options "SAMEORIGIN" always;