TinyMce view html issue when using a conditional html

When I view source of the tiny-mce plugin and add the following code, next time when I click button to see HTML source code it gives me following error.

HTML

<h3><!-- [if gte mso 9]><xml>
</xml><![endif]--> 
<div class="content">
All my content goes here.
</div>

Error

Uncaught HierarchyRequestError: Failed to execute 'insertNode' on 'Range': The node to be inserted contains a 'SPAN' node, which may not be inserted here.

Already tried

When i add an empty container just like this, it fixes the problem.

<p></p>
<h3><!-- [if gte mso 9]><xml>
</xml><![endif]--> 
<div class="content">
All my content goes here.
</div>