diff --git a/debian/marquee/DOMAINS b/debian/marquee/DOMAINS
index aaba58e..baeac84 100644
--- a/debian/marquee/DOMAINS
+++ b/debian/marquee/DOMAINS
@@ -13,6 +13,7 @@ fetch.spec.whatwg.org
 figures.idea.whatwg.org
 figures.spec.whatwg.org
 forums.whatwg.org
+fs.spec.whatwg.org
 fullscreen.spec.whatwg.org
 help.whatwg.org
 html-differences.whatwg.org
diff --git a/debian/marquee/nginx/sites/fs.spec.whatwg.org.conf b/debian/marquee/nginx/sites/fs.spec.whatwg.org.conf
new file mode 100644
index 0000000..050bfea
--- /dev/null
+++ b/debian/marquee/nginx/sites/fs.spec.whatwg.org.conf
@@ -0,0 +1,6 @@
+server {
+    server_name fs.spec.whatwg.org;
+    root /var/www/fs.spec.whatwg.org;
+
+    include /etc/nginx/whatwg.conf;
+}
diff --git a/test/certs.mjs b/test/certs.mjs
index 2e1d14b..3f14d79 100644
--- a/test/certs.mjs
+++ b/test/certs.mjs
@@ -21,6 +21,7 @@ const DOMAINS = [
   'figures.idea.whatwg.org',
   'figures.spec.whatwg.org',
   'forums.whatwg.org',
+  'fs.spec.whatwg.org',
   'fullscreen.spec.whatwg.org',
   'help.whatwg.org',
   'html-differences.whatwg.org',