DOM Snapshot Download bookmarklet

javascript: /*DOMSnapshotDownload*/ (rl => {
  function htm(t, m, a, c, x) {
    if(document.head && !document.head.querySelector("base")) {
      (x = document.createElement("BASE")).href = location.href.split("?")[0];
      document.head.appendChild(x)
    } else x = null;
    t = true;
    c = document.contentType;
    m = Array.from(document.childNodes).map((nd, i) => {
      switch (nd.nodeType) {
        case Node.COMMENT_NODE:
        case Node.TEXT_NODE:
          return `<!--${nd.data}-->\n`;
        case Node.ELEMENT_NODE:
          return nd.outerHTML + "\n";
        case Node.DOCUMENT_TYPE_NODE:
          t = !(nd.publicId || nd.systemId);
          return `<!${(/\bxml\b/).test(c) ? "DOCTYPE" : "doctype"} ${nd.name}${
            nd.publicId ? ` PUBLIC "${nd.publicId}"` : ""
          }${nd.systemId ? ` "${nd.systemId}"` : ""}>\n`;
        default:
          console.log("Unprocessed node", nd);
          return `<!--(NodeType${nd.nodeType})-->\n`
      }
    });
    if(document instanceof XMLDocument) {
      m.unshift(`<?xml version="1.0" encoding="${document.characterSet}" standalone="${t ? "yes" : "no"}"?>\n`)
    }
    rl.forEach(r => {
      r[1].parentNode.insertBefore(r[0], r[1]);
      r[1].parentNode.removeChild(r[1])
    });
    a = document.createElement("A");
    a.href = URL.createObjectURL(new Blob(m, {type: c}));
    if(!c.includes("xml")) {
      if(x) x.parentNode.removeChild(x);
      if(t = document.title) {
        x = {
          "\"": "\u201c",
          "*": "\u20f0",
          "/": "-",
          ":": "\ua789",
          "<": "\u2264",
          ">": "\u2265",
          "?": "\xbf",
          "\\": "-",
          "|": "\u2502"
        };
        t = t.replace(/["*\/:<>?\\|]/g, c => x[c]) + " - "
      }
      if (!(m = (m = location.pathname.match(/\/([^\/]+)$/)) ? m[1] : "")) t = t.replace(/ - $/, "");
      a.download = t + ((/\.html?$/i).test(m)
        ? m
        : m + "." + ([["xhtml", "xhtml"], ["html", "html"], ["xml", "xml"], ["text", "txt"]].reduce((r, k) => {
          if(!r && c.includes(k[0])) r = k[1];
          return r
        }, "") || "bin"));
      a.target = "_blank";
      a.click()
    } else open(a.href, "_blank")
  }
   function subsEle(ri, u, h, e) {
    e = document.createElement(rl[ri].href ? "style" : "script");
    e.setAttribute("source", u);
    e.innerHTML = h;
    rl[ri] = [rl[ri], e];
    rl[ri][0].parentNode.insertBefore(e, rl[ri][0]);
    rl[ri][0].parentNode.removeChild(rl[ri][0]);
    if(++ri < rl.length) {
      getRes(ri)
    } else htm()
  }
  function getRes(ri, u) {
    u = rl[ri].href || rl[ri].src;
    console.log("Fetching: " + u);
    fetch(u).catch((er, e) => {
      console.log("Error fetching: " + u, er);
      alert(`Error fetching:\n${u}\n\n${er}`);
      subsEle(ri, u, `/* ${er} */`)
    }).then(r => r.text()).then((t, e) => {
      console.log("Fetched: " + u);
      subsEle(ri, u, t)
    })
  }
  rl = Array.from(document.querySelectorAll("link[href][rel=stylesheet],script[src]")).filter(e => e.href || e.src);
  if(rl.length) {
    getRes(0)
  } else htm()
})()