logos.length == 0) {
            gitbook.toolbar.createButton({
                icon: 'nats',
                label: 'NATS Home Page',
                position: 'right',
                onClick: function () {
                    var win = window.open("https://nats.io/", '_blank');
                    win.focus();
                }
            });
        }

        document.querySelectorAll('.js-copy').forEach(elem => {
            elem.addEventListener("click", function () {
                var el = this;
