Problem on HTML tag statement with single quotation when switch back and forth between "Edit Html" and "Compose" modes

When create/edit a post, you have 2 ways: "Edit Html" and "Compose". When you enter HTML directly under the "Edit Html" tab, and switch back and forth between "Edit Html" and "Compose", watch out. As an example, when you enter HTML like next statement under the "Edit Html" tab:

<span class='menuButton' href='' onclick='return buttonClick(event,"tocMenu");' onmouseover='buttonMouseover(event,"tocMenu");'>Table of Conents</span>

Switch to "Compose" mode, and come back to "Edit Html" mode, it becomes like:

<span class="menuButton" onmouseover="'buttonMouseover(event," onclick="'return" href="">Table of Conents</span>

Once again, it tries to replace single quotation to double quotation, but it failed to pursue propery. So, to be safeside, use double quotation, instead of single quotation, on HTML tag statement when you create/edit post.