diff --git a/ace-window.el b/ace-window.el
index b89daf6..e7c78b4 100644
--- a/ace-window.el
+++ b/ace-window.el
@@ -431,7 +431,7 @@ The new frame is set to the same size as the previous frame, offset by
               (avy-mouse-event-window char)))
         ((= char (aref (kbd "C-g") 0))
          (throw 'done 'exit))
-        ((= char aw-make-frame-char)
+        ((and aw-make-frame-char (= char aw-make-frame-char))
          ;; Make a new frame and perform any action on its window.
          (let ((start-win (selected-window))
                (end-win (frame-selected-window (aw-make-frame))))