title: Using Custom UI editor insert a new tab as the last tab in Excel Ribbon
body: <p>I want to insert a new tab after the last tab.  But the problem is that I don't know exactly what is the current last tab; it could be "Acrobat reader" or something else. How to accomplish this. I have that following code:</p>
  
  <pre><code>&lt;customUI xmlns="http://schemas.microsoft.com/office/2006/01/customui"&gt;
  &lt;ribbon startFromScratch="false"&gt;
  &lt;tabs&gt;
  &lt;tab id="MyCustomTab" label="MyTab" insertAfterMso="TabView"&gt;
  &lt;group id="customGroup1" label="First Tab"&gt;
  &lt;button id="customButton1" label="JG Button 1" imageMso="HappyFace" size="large" onAction="Callback1" /&gt;
  &lt;button id="customButton2" label="JG Button 2" imageMso="PictureBrightnessGallery" size="large" onAction="Callback2" /&gt;
  &lt;/group&gt;
  &lt;/tab&gt;
  &lt;/tabs&gt;
  &lt;/ribbon&gt;
  &lt;/customUI&gt;
  </code></pre>