diff --git a/nextcloud.subdomain.conf.sample b/nextcloud.subdomain.conf.sample
index 27c2ea5..2e419f5 100644
--- a/nextcloud.subdomain.conf.sample
+++ b/nextcloud.subdomain.conf.sample
@@ -32,6 +32,7 @@ server {
         proxy_pass $upstream_proto://$upstream_app:$upstream_port;
 
         proxy_hide_header X-Frame-Options;
+        add_header X-Frame-Options "SAMEORIGIN";
         proxy_max_temp_file_size 2048m;
     }
 }