diff --git a/share/functions/funced.fish b/share/functions/funced.fish
index 88688b137..e9248f879 100644
--- a/share/functions/funced.fish
+++ b/share/functions/funced.fish
@@ -81,7 +81,7 @@ function funced --description 'Edit function definition'
         return 0
     end
 
-    set tmpname (mktemp -t fish_funced.XXXXXXXXXX)
+    set tmpname (mktemp -t fish_funced.XXXXXXXXXX.fish)
 
     if functions -q -- $funcname
         functions -- $funcname > $tmpname