Viewing master compatibility as a stack instead of stairstep

My Glyphs app used to show the different masters as a stack, one master on top of the other. Recently it switched to showing the masters side by side stair step like on an angle. What is the key command to switch back and forth for the two different views, stacked and stepped?

That’s in Preferences > User Settings. You’ll find a check box.

Ahhh. Thanks Toshi!