title: Copied dropdown menu doesn't work on one page mobile/tablet devices
body: <p>I'm using bootstrap 3 to build a website. I've built a dropdown menu for mobile and tablet devices and I have the following problem. The drop-down menu works on every site except "Referenzen". But the code is copied, so it's the exactly same on each site.</p>
  
  <p>Here's my code. You can try it on <a href="http://jenquisi.bplaced.net/" rel="nofollow noreferrer">http://jenquisi.bplaced.net/</a></p>
  
  <p>It works perfectly on PC. I'd be glad if you could help me! </p>
  
  <pre><code>&lt;div class="dropdown visible-xs"&gt;
      &lt;img class="dropdown_img" src="img/dropdown.png" alt="dropdown_icon" data-toggle="dropdown"&gt;
      &lt;ul class="dropdown-menu"&gt;
          &lt;li&gt;&lt;a href="index.html"&gt;Home&lt;/a&gt;&lt;/li&gt;
          &lt;li&gt;&lt;a href="about.html"&gt;Über uns&lt;/a&gt;&lt;/li&gt;
          &lt;li&gt;&lt;a href="service.html"&gt;Leistungen&lt;/a&gt;&lt;/li&gt;
          &lt;li&gt;&lt;a href="reference-alt.html"&gt;Referenzen&lt;/a&gt;&lt;/li&gt;
          &lt;li&gt;&lt;a href="contact-map.html"&gt;Kontakt&lt;/a&gt;&lt;/li&gt;
          &lt;li&gt;&lt;a href="#"&gt;Neuigkeiten&lt;/a&gt;&lt;/li&gt;
      &lt;/ul&gt;
  &lt;/div&gt;
  </code></pre>