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/*
** From http://stackoverflow.com/questions/1119289/how-to-show-the-are-you-sure-you-want-to-navigate-away-from-this-page-when-ch
*/

var confirmOnPageExit = function (e) {
    // If we haven't been passed the event get the window.event
    e = e || window.event;

    var message = 'Any text will block the navigation and display a prompt';

    // For IE6-8 and Firefox prior to version 4
    if (e) 
    {
        e.returnValue = message;
    }

    // For Chrome, Safari, IE8+ and Opera 12+
    return message;
};

// Turn it on - assign the function that returns the string
window.onbeforeunload = confirmOnPageExit;

// Turn it off - remove the function entirely
//window.onbeforeunload = null;