If you follow Louis's instructions on this topic, you might get stuck on step 6. Paste the following script instead of the one on cloak.ist. Syntax fix - save for later.

const config = {
  subdomain: "blog.example.com",
  root: "example.com",
  blogPath: "blog",
};

async function handleRequest(request) {
  const url = new URL(request.url);
  const targetPath = url.pathname;
  let response = await fetch(https://</span><span class=si>${</span><span class=nx>config</span><span class=p>.</span><span class=nx>subdomain</span><span class=si>}${</span><span class=nx>targetPath</span><span class=si>}</span><span class=sb>);


  if (
    targetPath.includes(/</span><span class=si>${</span><span class=nx>config</span><span class=p>.</span><span class=nx>blogPath</span><span class=si>}</span><span class=sb>/favicon.png) ||
    targetPath.includes(/</span><span class=si>${</span><span class=nx>config</span><span class=p>.</span><span class=nx>blogPath</span><span class=si>}</span><span class=sb>/sitemap.xsl) ||
    targetPath.includes(/</span><span class=si>${</span><span class=nx>config</span><span class=p>.</span><span class=nx>blogPath</span><span class=si>}</span><span class=sb>/assets/) ||
    targetPath.includes(/</span><span class=si>${</span><span class=nx>config</span><span class=p>.</span><span class=nx>blogPath</span><span class=si>}</span><span class=sb>/public/) ||
    targetPath.includes(/</span><span class=si>${</span><span class=nx>config</span><span class=p>.</span><span class=nx>blogPath</span><span class=si>}</span><span class=sb>/content/)
  ) {
    return response;
  }


  let body = await response.text();
  body = body.split(config.subdomain).join(config.root);
  response = new Response(body, response);
  return response;
}


addEventListener("fetch", (event) => {
  event.respondWith(handleRequest(event.request));
});