When you try to close the main browser window using the close [ window.close(); ] method. You get the confirmation prompt

The Web page you are viewing is trying to close the window.
 Do you want to close the window?

This warnning message appears only if you are trying to close the main browser window and not the popups. To stop this use the following snippet
function closeMe(){
window.opener = "";
window.close();
}
It works because the browser checks for the value of window.opener to see if it is a child window or main window. if the value is null then it assumes the window to be main window. Now we are cheating the browser by assigning the window.opener to some random value!