script>
setup({explicit_done: true});
let iframe;
function setup_iframe() {
    const iframe_content =
        '<script src="empty_script.js?id=1"></scr' + 'ipt>' +
        '<script src="empty_script.js?id=2" async></scr' + 'ipt>' +
        '<script src="empty_script.js?id=3" async=false></scr' + 'ipt>' +
        '<script src="empty_script.js?id=4" defer></scr' + 'ipt>' +
        '<script>' +
        'document.write("<script src=\\"empty_script.js?id=5\\"></scr" + "ipt>");' +
        'const s1 = document.cr