title: tabindex issue with select2
body: <p>I am having an issue with the taborder on my form whilst using select2.</p>
  
  <p>I have an input form that I want the user to be able to tab through in order.</p>
  
  <p>I have been able to order the text input fields but not select2 dropdownlists.</p>
  
  <p>It appears the issue is with them having a default tabindex="-1", as below;</p>
  
  <pre><code>&gt;  &lt;div id="s2id_ctl00_MainContent_ddlAreaKept" class="select2-container
  &gt; form-control"&gt;
  &gt;     &lt;a class="select2-choice" tabindex="-1" onclick="return false;" href="javascript:void(0)"&gt;
  &gt;     &lt;input id="s2id_autogen4" class="select2-focusser select2-offscreen" type="text" tabindex="0"&gt;
  &gt;     &lt;div class="select2-drop select2-display-none select2-with-searchbox"&gt;
  &gt;     &lt;/div&gt;
  &gt;     &lt;select id="ctl00_MainContent_ddlAreaKept" class="form-control select2-offscreen" name="ctl00$MainContent$ddlAreaKept" tabindex="-1"&gt;
  </code></pre>
  
  <p>I have also written the following javascript to add tabIndex values to the fields but it isn't working how I'd like.</p>
  
  <pre><code>   var tabOrder = 0;
  
  document.getElementById("ctl00_MainContent_ddlAreaKept").tabIndex = tabOrder++;
  document.getElementById("ctl00_MainContent_ddlNCDYears").tabIndex = tabOrder++;
  document.getElementById("ctl00_MainContent_txtVehicleValue").tabIndex = tabOrder++;
  document.getElementById("ctl00_MainContent_txtAge").tabIndex = tabOrder++;
  document.getElementById("ctl00_MainContent_txtForename").tabIndex = tabOrder++;
  document.getElementById("ctl00_MainContent_txtSurname").tabIndex = tabOrder++;
  document.getElementById("ctl00_MainContent_txtEmail").tabIndex = tabOrder++;
  document.getElementById("ctl00_MainContent_txtPhoneNumber").tabIndex = tabOrder++;
  document.getElementById("ctl00_MainContent_btnGetQuote").tabIndex = tabOrder++;
  </code></pre>
  
  <p>The dropdownlists don't get tabbed into, it skips them and goes through the textboxes as it should.</p>
  
  <p>Any help much appreciated!</p>
  
  <p>SOLVED : I tried:</p>
  
  <pre><code>var tabOrder = 1;
  </code></pre>
  
  <p>and this has solved the issue.  I don't exactly know why or how :|</p>