Why empty space in CSS table-cells?

Question

Why does the cells left and right get filled with empty space?

The empty space is above the left and right table-cell.

http://jsfiddle.net/Tim86/NU9sA/

It has something to do with the #middlebuttons{display:block;}.

EDIT: I am using Firefox 5.

EDIT2: Pictues

Wrong

Right

Answer 1

I think it's this bug in Firefox. The workaround seems to be to add the following:

#middleButtons {
    vertical-align:top;
}

Was looking at this for a while in Chrome and couldn't see the problem!