Since I haven't bought/sold anything with the new Express system yet, this was a pretty easy find. If you do not have an order history and go to the order history page, then an expand arrow will appear despite there being nothing to expand. Clicking on the "Buy History" tab or clicking the expand arrow will cause the expand arrow to disappear. It will reappear if you leave and return to the order history page. This is presumably also the case with the "Sell History" tab in the order history page, but since you must click the "Sell History" tab to navigate to it the arrow would disappear.
Navigating from another page to the Orders page.
Clicking "Buy History" or the expand arrow.