<!DOCTYPE html>
<html lang="en-US">
  <head>
    <title>Slot content test</title>
    <meta charset="UTF-8" />
  </head>
  <body>
    <main id="main">
      <div id="no-host">
          <a href='http://google.com'>Google</a>
      </div>
      <div id="host">
         <span>IBM</span>
      </div>
    </main>
    <script type="text/javascript">
      let shadow = document
        .getElementById("host")
        .attachShadow({ mode: "open" });
      let div1 = document.createElement("div");
      div1.setAt