diff --git a/data/filetype_extensions.conf b/data/filetype_extensions.conf
index d8dc26e89c..ce28c66fa9 100644
--- a/data/filetype_extensions.conf
+++ b/data/filetype_extensions.conf
@@ -42,7 +42,7 @@ Haskell=*.hs;*.lhs;*.hs-boot;*.lhs-boot;
 Haxe=*.hx;
 HTML=*.htm;*.html;*.shtml;*.hta;*.htd;*.htt;*.cfm;*.tpl;
 Java=*.java;*.jsp;
-Javascript=*.js;
+Javascript=*.js;*.mjs;
 JSON=*.json;
 Julia=*.jl;
 Kotlin=*.kt;*.kts;