Split View in Mission Control
5 Open Mission Control and then drag a window from your current desktop space and drop it on an app that’s already in full-screen mode in the Spaces bar at the top of the screen. They will be combined in Split View. Drop the window on the left- or right-hand side of the space’s thumbnail to choose which side of the screen it should occupy. If you change your mind, you can switch them around by clicking on one’s toolbar and then dragging it across the screen. To remove both apps from Split View, put the pointer over it in Mission Control’s Spaces bar and then click the inward-pointing arrows at its top-left corner.