Possible bug: HTML-code removed from widget when editing

I need to have html in some of the widgets that I have on my site.

Example:

<a href="url">
<div>logo</div>
<div>text</div>
</a>

This code is inserted in the text editor and works great.

But when I edit the same widget again, it auto opens in visual editor and deletes the a-tags and replaces it with  .

Please let me know if this is a bug or if there are ways to avoid this.