dijit hovering MenuItem issue

Question

I have a dijit.layout.TabContainer on my form.

I resize the browser window in such a way that all tabs won't fit in a single screen. In this case dijit automatically adds a drop-down button at the right end of the TabContainer (I get this for free). If I click on the drop-down button then I get the full List of Tab Names.

Hovering over the List of Tab Names (which is in fact a collection of menu items) it blanks out the menu item name which I'm currently over. e.g.

Full List:
Tab1
Tab2
Tab3

Hovering over Tab2 I get:
Tab1

Tab3

I get the same issue with any other dijit.Menu, dijit.MenuItem AND I get the same issue on IE, Firefox, Chrome. I haven't tested on any other browser.

Thanks.