diff --git a/src/index.ts b/src/index.ts
index 2f21958..a749f6c 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -56,7 +56,7 @@ app.use('/api-doc', helmet.contentSecurityPolicy({
   }
 }));
 // special CSP header for the intro-presentation
-app.use('/static/intro-presentation/$|index.html', helmet.contentSecurityPolicy({
+app.use(/\/static\/intro-presentation\/(index.html)?/, helmet.contentSecurityPolicy({
   ...defaultHeaderConfig,
   directives: {
     defaultSrc: [`'none'`],