diff --git a/rc/extra/moon.kak b/rc/extra/moon.kak
index 98658cd9..90f5d59c 100644
--- a/rc/extra/moon.kak
+++ b/rc/extra/moon.kak
@@ -11,7 +11,7 @@ hook global BufSetOption mimetype=text/x-moon %{
 }
 
 hook global BufCreate .*[.](moon) %{
-    set buffer filetype moon
+    set buffer mimetype text/x-moon
 }
 
 # Highlighters