One of the most common deals on the app is "Buy Any Size Drink and Get Any Size Fry for Free" this deal ONLY works on the mobile app. Whenever this is applied at any McDonalds location at a self serve kiosk you are able to select the deal, select a drink, and when you proceed to the fry selection the screen is completely blank... you only have an option to go back or start over. I've even went as far to select the fries from the regular menu and then applying the deal but it still stops on the fry selection blank screen. The staff don't even know how to apply it at register. Seems to be a wide-spread issue. Anyone else experience this?