title: Bootstrap 4 - Toggle button not working
body: <p>I'm trying to add <code>navbar</code> to my website, but when I add it toggle button doesn't work. </p>
  
  <p>Here is my <code>navbar</code> code:</p>
  
  <pre><code>&lt;nav class="navbar navbar-expand-lg navbar-light bg-light"&gt;
    &lt;a class="navbar-brand" href="#"&gt;Navbar&lt;/a&gt;
    &lt;button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation"&gt;
      &lt;span class="navbar-toggler-icon"&gt;&lt;/span&gt;
    &lt;/button&gt;
  
    &lt;div class="collapse navbar-collapse" id="navbarSupportedContent"&gt;
      &lt;ul class="navbar-nav mr-auto"&gt;
        &lt;li class="nav-item active"&gt;
          &lt;a class="nav-link" href="#"&gt;Home &lt;span class="sr-only"&gt;(current)&lt;/span&gt;&lt;/a&gt;
        &lt;/li&gt;
        &lt;li class="nav-item"&gt;
          &lt;a class="nav-link" href="#"&gt;Link&lt;/a&gt;
        &lt;/li&gt;
        &lt;li class="nav-item"&gt;
          &lt;a class="nav-link disabled" href="#"&gt;Disabled&lt;/a&gt;
        &lt;/li&gt;
      &lt;/ul&gt;
      &lt;form class="form-inline my-2 my-lg-0"&gt;
        &lt;input class="form-control mr-sm-2" type="text" placeholder="Search" aria-label="Search"&gt;
        &lt;button class="btn btn-outline-success my-2 my-sm-0" type="submit"&gt;Search&lt;/button&gt;
      &lt;/form&gt;
    &lt;/div&gt;
  &lt;/nav&gt; 
  </code></pre>
  
  <p>Here is what I've included:</p>
  
  <pre><code>&lt;link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" integrity="sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M" crossorigin="anonymous"&gt;
  &lt;script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/js/bootstrap.min.js" integrity="sha384-h0AbiXch4ZDo7tp9hKZ4TsHbi047NrKGLO3SEJAg45jXxnGIfYzk4Si90RDIqNm1" crossorigin="anonymous"&gt;&lt;/script&gt;
  &lt;script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"&gt;&lt;/script&gt;
  &lt;script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.11.0/umd/popper.min.js" integrity="sha384-b/U6ypiBEHpOf/4+1nzFpr53nxSS+GLCkfwBdFNTxtclqqenISfwAzpKaMNFNmj4" crossorigin="anonymous"&gt;&lt;/script&gt;
  </code></pre>
  
  <p>Thanks for help!</p>