Okidoki
. Pull down the notification bar so you get tiles.
Tap the immersive tile to turn immersive mode on. Press the two little squares in the top right corner of the immersive tile and it will enable the ability to change where you want the immersion to effect. By swiping up/down on the immersive tile will toggle through the options of full/statusbar/navigation bar
Pick navigation bar. Tap the two squares again and it should now state immersive. Just then swipe up from the bottom of the screen to activate pie.
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