如何使用Bootstrap dropdown.js作为单机版？

<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/css/bootstrap.min.css">
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/js/bootstrap.bundle.min.js"></script>

<button class="btn btn-primary dropdown-toggle" type="button" id="dropdownMenuButton" data-bs-toggle="dropdown" aria-expanded="false">
  下拉菜单
</button>

<ul class="dropdown-menu" aria-labelledby="dropdownMenuButton">
  <li><a class="dropdown-item" href="#">菜单项1</a></li>
  <li><a class="dropdown-item" href="#">菜单项2</a></li>
  <li><a class="dropdown-item" href="#">菜单项3</a></li>
</ul>

var dropdownElementList = [].slice.call(document.querySelectorAll('.dropdown-toggle'))
var dropdownList = dropdownElementList.map(function (dropdownToggleEl) {
  return new bootstrap.Dropdown(dropdownToggleEl)
});