title: DataTables: Uncaught TypeError: Cannot read property 'buttons' of undefined
body: <p>I am having trouble setting up a custom dataTables that uses the Buttons plugin.</p>
  
  <p>I can set up a <a href="https://datatables.net/manual/options#Setting-defaults" rel="noreferrer">custom default</a> <code>dom</code> layout that works:</p>
  
  <pre><code>//vanilla dom (frtip...)
  $.extend($.fn.dataTable.defaults, {
    dom: 'frtip'
  });
  </code></pre>
  
  <p>But if I try to <a href="https://datatables.net/extensions/buttons/#dom-parameter" rel="noreferrer">include the "B" character in the <code>dom</code> layout</a>: </p>
  
  <pre><code>// Invoke Buttons plugin (Bfrtip...)
  $.extend($.fn.dataTable.defaults, {
    dom: 'Bfrtip'
  });
  </code></pre>
  
  <p>...then run dataTables, this JavaScript error is reported:</p>
  
  <blockquote>
    <p>Uncaught TypeError: Cannot read property 'buttons' of undefined</p>
  </blockquote>
  
  <p>What am I doing wrong?</p>
  
  <p>Please <a href="https://jsfiddle.net/jhfrench/at83rcoL/" rel="noreferrer">see an example of this at https://jsfiddle.net/jhfrench/at83rcoL/</a></p>