title: How to add dropdown menu on tab / tabset [rmarkdown / bootstrap]
body: <p>Documentation for Bootswatch suggests I can use a dropdown menu from a tab in a tabset:</p>
  
  <p><a href="https://i.stack.imgur.com/294eX.png" rel="noreferrer"><img src="https://i.stack.imgur.com/294eX.png" alt="enter image description here"></a></p>
  
  <p>How can I achieve this with Rmarkdown? I've tried:</p>
  
  <pre><code># SECTION 1 {.tabset .tabset-fade}
  
  ## Section 1.1 
  
  ## Section 1.2 {????something here?????}
   ### Section 1.2.1  &lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt; want this to appear under the dropdown menu
  </code></pre>