rapids/docs/overrides/partials/integrations/utterances.html

<!-- Utterances integration -->
{% if not page.is_homepage %}
  <h2 id="__comments">{{ lang.t("meta.comments") }}</h2>

   <script type="text/javascript">
    var rapids_utterances_theme = false
    document.onreadystatechange = function () {
        if (document.readyState == "interactive") {
          // wait for utterances to load and send it's first message.
          addEventListener('message', event => {
            if (event.origin !== 'https://utteranc.es' || rapids_utterances_theme == true) {
              return;
            }
            rapids_utterances_theme = true
            if(document.body.getAttribute("data-md-color-scheme") == "default")
              document.querySelector("iframe.utterances-frame").contentWindow.postMessage({ type: "set-theme", theme: "github-light" },"https://utteranc.es/")
            else
              document.querySelector("iframe.utterances-frame").contentWindow.postMessage({ type: "set-theme", theme: "photon-dark" },"https://utteranc.es/")
          });
          document.getElementById('__palette_1').onclick = function(){
            document.querySelector("iframe.utterances-frame").contentWindow.postMessage({ type: "set-theme", theme: "github-light" },"https://utteranc.es/")
          }
          document.getElementById('__palette_2').onclick = function(){
            document.querySelector("iframe.utterances-frame").contentWindow.postMessage({ type: "set-theme", theme: "photon-dark" },"https://utteranc.es/")
          }
        }
      }
  </script>

  <script src="https://utteranc.es/client.js"
    repo="carissalow/rapids"
    issue-term="pathname"
    label="docs comments"
    theme="github-light"
    crossorigin="anonymous"
    async>
  </script>
{% endif %}