diff --git a/nginx/snippets/security-headers-base.conf b/nginx/snippets/security-headers-base.conf
index a7669ca4..8fe43c17 100644
--- a/nginx/snippets/security-headers-base.conf
+++ b/nginx/snippets/security-headers-base.conf
@@ -3,6 +3,7 @@ add_header X-Content-Type-Options "nosniff" always;
 add_header Referrer-Policy "no-referrer" always;
 add_header Cross-Origin-Opener-Policy "same-origin" always;
 add_header Cross-Origin-Embedder-Policy "require-corp" always;
+add_header Origin-Agent-Cluster "?1" always;
 
 # obsolete when client system time is correct
 add_header Expect-CT "enforce, max-age=63072000" always;