diff --git a/_headers b/_headers
index 7dd9d54..2ab126d 100644
--- a/_headers
+++ b/_headers
@@ -1,6 +1,6 @@
 /
   Strict-Transport-Security : max-age=63072000; includeSubDomains; preload
-  Content-Security-Policy : default-src 'self'; font-src 'self' fonts.gstatic.com; style-src 'self' fonts.googleapis.com; script-src 'self' 'unsafe-inline'; form-action 'none'; frame-ancestors 'none'; block-all-mixed-content; base-uri 'none'
+  Content-Security-Policy : default-src 'self'; font-src 'self' fonts.gstatic.com; style-src 'self' fonts.googleapis.com; script-src 'self' 'unsafe-inline'; form-action 'none'; frame-ancestors 'none'; upgrade-insecure-requests; block-all-mixed-content; base-uri 'none'
   X-Content-Type-Options : nosniff
   Referrer-Policy : no-referrer
   X-Frame-Options : DENY