diff --git a/vendor/docker/webapp.conf b/vendor/docker/webapp.conf
index 9e6cc1e..f40aea3 100644
--- a/vendor/docker/webapp.conf
+++ b/vendor/docker/webapp.conf
@@ -9,7 +9,7 @@ server {
     merge_slashes off;
 
     location / {
-        add_header 'Access-Control-Allow-Origin: *' always;
-        add_header 'Access-Control-Allow-Headers: Content-Type,Accept,Accept-Encoding,Origin,User-Agent,Cache-Control,Keep-Alive' always;
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header 'Access-Control-Allow-Headers' 'Content-Type,Accept,Accept-Encoding,Origin,User-Agent,Cache-Control,Keep-Alive' always;
     }
 }