chromium/third_party/blink/web_tests/external/wpt/css/css-content/quotes-slot-scoping.html

<!DOCTYPE html>
<html>
  <head>
    <title>Quote scope Shadow DOM and SLOT</title>
    <link rel="author" title="Martin Robinson" href="mailto:[email protected]">
    <link rel="help" href="https://www.w3.org/TR/css-content-3/#quote-values">
    <link rel="match" href="quotes-slot-scoping-ref.html">
  </head>

  <body>
    <div id="host">
      <q slot="quote">Quote</q>
    </div>

    <script>
      function makeStyle() {
        let style = document.createElement('style');
        style.textContent = `
            q {
              quotes: '1' '1' '2' '2' '3' '3';
            }
        `;
         return style;
      }
      document.body.appendChild(makeStyle());

      const shadowRoot = document
           .getElementById('host')
           .attachShadow({mode: 'open'});
      shadowRoot.innerHTML = `
      <q>
        <slot name="quote"></slot>
      </q>
      `;
      shadowRoot.appendChild(makeStyle());
    </script>
  </body>
</html>