minor ui fullscreen fix, for explorer menu
minor ui fullscreen fix, for explorer menu

Microsoft/pxt,Microsoft/pxt,switch-education/pxt,Microsoft/pxt,switch-education/pxt,playi/pxt,switchinnovations/pxt,switch-education/pxt,playi/pxt,switchinnovations/pxt,switchinnovations/pxt,switch-education/pxt,playi/pxt,switch-education/pxt,Microsoft/pxt,playi/pxt,switchinnovations/pxt,Microsoft/pxt