diff --git a/runtime/makemenu.vim b/runtime/makemenu.vim
index 4dfd2cc..4de9d48 100644
--- a/runtime/makemenu.vim
+++ b/runtime/makemenu.vim
@@ -678,6 +678,7 @@
 SynMenu WXYZ.YAML:yaml
 SynMenu WXYZ.Yacc:yacc
 SynMenu WXYZ.Zimbu:zimbu
+SynMenu WXYZ.Zserio:zserio
 
 append(lnum, "")