diff --git a/lisp/ido.el b/lisp/ido.el
index 47cbcb63c69..4f1e36ba914 100644
--- a/lisp/ido.el
+++ b/lisp/ido.el
@@ -4701,7 +4701,7 @@ Modified from `icomplete-completions'."
     (if (and ido-use-faces comps)
 	(let* ((fn (ido-name (car comps)))
 	       (ln (length fn)))
-	  (setq first (format "%s" fn))
+	  (setq first (copy-sequence fn))
 	  (put-text-property 0 ln 'face
 			     (if (= (length comps) 1)
                                  (if ido-incomplete-regexp