diff --git a/suite/common/pref/pref-applications-edit.xul b/suite/common/pref/pref-applications-edit.xul
index a5ef292846dc..3e5369febd8b 100644
--- a/suite/common/pref/pref-applications-edit.xul
+++ b/suite/common/pref/pref-applications-edit.xul
@@ -334,7 +334,7 @@
           dialogMsg = dialogMsg.replace(/%mime%/g, gMIMEField.value);
           var replace = promptService.confirm(window, titleMsg, dialogMsg);
           if (!replace)
-            window.close();
+            return true;
           
           // delete mimetype we're overwriting
           if (gMIMEField.value)