 let start_time = (+new Date());
            
            var xhr = new XMLHttpRequest();
            xhr.open('GET', '/cgi-bin/luci/admin/services/openclash/website_check?domain=' + encodeURIComponent(domain), true);
            xhr.timeout = 10000;
            
            xhr.onreadystatechange = function() {
                if (xhr.readyState === 4) {
                    let response_time = (new Date()) - start_time;
                    
                    if (xhr.status === 200) {
                    