Is it possible to override the Backstage tab item widths? I have a couple of tabs where the text is being clipped because it's too long. I tried setting the width property of the BackstageTab to compensate, which does work - *except* the container doesn't expand itself to the new size of the tab item, it remains fixed, and tab item is clipped instead (the little white selected arrow is no longer visible). HorizontalAlignment=Stretch doesn't work either. Am I missing something obviousy (still trying to get my head around the WPF way of doing things) or is this not as straightforward as I'm expecting it to be?