diff --git a/src/gateway/mime.types.conf b/src/gateway/mime.types.conf
index 89be9a4cd6..f2e68120c4 100644
--- a/src/gateway/mime.types.conf
+++ b/src/gateway/mime.types.conf
@@ -6,6 +6,7 @@ types {
     image/gif                             gif;
     image/jpeg                            jpeg jpg;
     application/javascript                js;
+    application/javascript                mjs;
     application/atom+xml                  atom;
     application/rss+xml                   rss;