Fix z-index in preview popout button
Fix z-index in preview popout button

Was being occluded by preview frame

outoftime/learnpad,jwang1919/popcode,popcodeorg/popcode,outoftime/learnpad,jwang1919/popcode,popcodeorg/popcode,jwang1919/popcode,jwang1919/popcode,popcodeorg/popcode,popcodeorg/popcode