Ok, I am using Chrome for this.
I have a div on which i defined display: -webkit-box;. Inside of this div there are 7 divs which all have -webkit-box-flex: 1;.
The first div, however, is smaller than the others. Any thoughts anyone?
Appearantly I misunderstood the box model. I was confused at the time and thought all divs would be equal, but actually it is the remaining space that is being added equally.