--- a/toolkit/components/downloads/src/nsDownloadManagerUI.js
+++ b/toolkit/components/downloads/src/nsDownloadManagerUI.js
@@ -96,17 +96,17 @@ nsDownloadManagerUI.prototype = {
   {
     if (!this.visible)
       throw Cr.NS_ERROR_UNEXPECTED;
 
     var prefs = Cc["@mozilla.org/preferences-service;1"].
                 getService(Ci.nsIPrefBranch);
     var flashCount = prefs.getIntPref(PREF_FLASH_COUNT);
 
-    var win = this.recentWindow.QueryInteface(Ci.nsIDOMChromeWindow);
+    var win = this.recentWindow.QueryInterface(Ci.nsIDOMChromeWindow);
     win.getAttentionWithCycleCount(flashCount);
   },
 
   //////////////////////////////////////////////////////////////////////////////
   //// nsDownloadManagerUI
 
   get recentWindow() {
     var wm = Cc["@mozilla.org/appshell/window-mediator;1"].