Script para poner un enlace en el texto que copien de mi blog

    function addLink() {
        var selection = window.getSelection(),
            pagelink = '<br /><br /> Fuente original: ' + document.location.href,
            copytext = selection + pagelink,
            newdiv = document.createElement('div');

        newdiv.style.position = 'absolute';
        newdiv.style.left = '-99999px';
        document.body.appendChild(newdiv);
        newdiv.innerHTML = copytext;
        selection.selectAllChildren(newdiv);

        window.setTimeout(function () {
            document.body.removeChild(newdiv);
        }, 100);
    }

    document.addEventListener('copy', addLink);