title: tinyMCE.execCommand('mceInsertContent' automatically getting undone
body: <p>When I am adding some text with tinyMCE.execCommand it appears for couple of seconds and then automatically undoes.</p>
  
  <p>Trying to understand how the undo level works.
  How to add undo/manage level?</p>
  
  <p>Striped down version of code used:</p>
  
  <pre><code>&lt;html&gt;
  &lt;head&gt;
      &lt;title&gt;TinyMCE editor&lt;/title&gt;
      &lt;script type="text/javascript" src="tiny_mce/tiny_mce.js"&gt;&lt;/script&gt;
      &lt;script type="text/javascript" src="jquery/jquery-1.10.2.js"&gt;&lt;/script&gt;
      &lt;script type="text/javascript" src="jquery/jquery-ui.js"&gt;&lt;/script&gt;
      &lt;script type="text/javascript"&gt;
          var toolbar =
                  "fontselect,fontsizeselect, formatselect, bold,italic,underline,|," +
                  "forecolor,backcolor,|,removeformat,cleanup,|,codemirror2,charmap,|,fullscreen";
  
          var toolbar2 =
                  "undo,redo,|,pastetext,pasteword,|,bullist,numlist,|,outdent,indent,|," +
                  "justifyleft,justifycenter,justifyright,justifyfull,|,link,unlink,anchor,image";
  
          var initHtmlMode = {
              mode: "textareas",
              theme: "advanced",
              theme_advanced_buttons1: toolbar,
              theme_advanced_buttons2: toolbar2,
              theme_advanced_toolbar_location: "top",
              theme_advanced_toolbar_align: "left",
              theme_advanced_statusbar_location: "bottom",
              theme_advanced_resizing: true
          };
  
          tinyMCE.init(initHtmlMode);
  
          function showList() {
              tinyMCE.execCommand('mceInsertContent', false, 'some text');
          }
      &lt;/script&gt;
  &lt;/head&gt;
  &lt;body&gt;
  &lt;form&gt;
      &lt;textarea id="content" rows="15" style="width: 80%"&gt;&lt;/textarea&gt;
      &lt;br/&gt;
      &lt;button onclick="showList()"&gt;Insert&lt;/button&gt;
  &lt;/form&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>