AIR window alwaysInFront preblem in MAC

Question

I am working in adobe flex 4.6 AIR application. I run my main application and click on button, a window is opened which is transparent, alwaysInFront="true", width and height of the screen. When it opens, i click on another buttons in my main application. The button click perform when i click 3 or 4 times on that in MAC but when i perform this in windows it working fine on single click. If i set the alwaysInFront="false" then it works fine in windows and MAC.

Window code is below

<?xml version="1.0" encoding="utf-8"?>
<s:Window xmlns:fx="http://ns.adobe.com/mxml/2009"
          xmlns:s="library://ns.adobe.com/flex/spark"
          xmlns:mx="library://ns.adobe.com/flex/mx"
          xmlns:customcomponents="customs.customcomponents.*"
          xmlns:services="services.*"
          width="100%" height="100%" backgroundAlpha="0"
          creationComplete="window1_creationCompleteHandler(event)"              minimizable="false" showStatusBar="false" systemChrome="none" transparent="true" alwaysInFront="true">

<mx:Canvas id="canDesktopVideo" width="100%" height="100%" horizontalScrollPolicy="off"
    verticalScrollPolicy="off"> 
</mx:Canvas>    

</s:Window>

So any one has any idea why alwaysInFront="true" in window create problem in MAC.