AS3 problem, are MAC and PC flashplayers different?

programming flash
1

Im using flash player 9.0.124.0 on both MAC and PC…

This below example works on my mac in both Safari and Firefox but does not work on a PC in IE or Firefox

var _fs:Boolean = false;
 
btn.addEventListener(MouseEvent.MOUSE_DOWN, toggleFullScreen),
 
function toggleFullScreen(e:MouseEvent){
    if(_fs == false){
         _fs == true;
    }else{
         _fs == false;
    }
    
    trace(_fs); // no mater how many times I click "btn" on a PC _fs remains false; 
 
}

If you can help that would be great :hat: