Comment 3 for bug 423151

Actually, the problem is partially in the description editing widget. I had to use z-index to get the tabs to stack correctly in the widget, and I would guess from the screenshot, the z-index of the description editor is higher than the error overlay.

I think I only used a z-index of 2, so maybe overlays could do some high number to always be on top. Or the description widget could be refactored to not rely on z-index. But I found this quite hard to do during initial development of this description editing widget.