我对 HTML 非常陌生，几个小时以来我一直在努力让我的下拉菜单正常工作。我搜索了许多面临类似问题的帖子，但仍然找不到并解决问题。我不确定问题是否也是由我的脚本引起的

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<script src="https://ajax.googleleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.16.0/umd/popper.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js"></script>

<header class="navbar navbar-expand-lg navbar-light bg-light">
  <a class="navbar-brand" href="#" id="logo">Logo</a>
  <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent">
        <span class="navbar-toggler-icon"></span>
        </button>

  <nav class="collapse navbar-collapse" id="navbarSupportedContent">
    <ul class="navbar-nav mr-auto">
      <li class="nav-item"><a class="nav-link active" href="#">Home <span class="sr-only">(current)</span></a></li>
      <li class="nav-item"><a class="nav-link" href="#">Link</a></li>
      <li class="nav-item">
        <div class="dropdown">
          <a href="#" class="nav-link dropdown-toggle" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Dropdown</a>
          <div class="dropdown-menu" aria-labelledby="navbarDropdown">
            <a href="#" class="dropdown-item">Action</a>
            <a href="#" class="dropdown-item">Another action</a>
            <div class="dropdown-divider"></div>
            <a href="#" class="dropdown-item">Something else here</a>
          </div>
        </div>
      </li>
      <li class="nav-item"><a class="nav-link" href="#">Disabled</a></li>
    </ul>
  </nav>
</header>

提前致谢！

我尝试用 data-bs-toggle="dropdown" 替换 data-toggle="dropdown" 但它不起作用，因为我使用的是 bootstrap 4，直接从 bootstrap 复制并粘贴代码，它仍然失败