a) Touch the
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b) If the current application supports split screen, there will be a split screen operation prompt at the top of the screen: “Swipe to corner to trigger float window/split screen”. Follow this prompt.
Method2:
Go to “Settings” -> “Button & gestures” -> “Gestures” -> “Split-screen gesture”, then in the home screen or applications supporting split screen, swipe up with 3 fingers on the screen to activate split mode.