add-favorite.js

$('#favorite').click(function(e){
    e.preventDefault();

    var url = 'http://github.com';
    var title = 'GitHub';
    var ctrl = (window.navigator.userAgent.toLowerCase()).indexOf('mac') !== -1 ? 'Command' : 'Ctrl';
    var info = 'Sorry, your browser is not supported. Please use' + ctrl + '+D to add favorite';

    try {
        window.external.addFavorite(url, title);
    } catch (ex) {
        try {
            window.sidebar.addPanel(url, title, "");
        } catch (exs) {
            alert(info);
        }
    }
});