test

[nianjiang]

As alex-shpak suggested, I used js in inject partials to un-collapse the menu.

---

The related code:
Find the id from html:

<li>
    <input type="checkbox" id="section-2d21464784c99358edd6d2b29e92ed6f" class="toggle" checked="">
    <label for="section-.." class="flex justify-between">
      <a href=".." class="active">..</a>
    </label>

Add js in themes/hugo-book/layouts/partials/docs/inject/footer.html

<script type="text/javascript">
    //Open menu after page loaded.
    document.getElementById("section-2d21464784c99358edd6d2b29e92ed6f").click();
</script>