Spritekit: How do I show time in scenekit action editor/timeline

Hello,


I'm pretty new to using SpriteKit. So I'm taking a course on it from Udemy.


The scenekit action editor/timeline that shows in this course shows second markings. But those second markings don't show in the Xcode I'm using.


Can anyone please tell me how to show the time markings on the scenekit action editor/timeline?


BTW, I'm using Xcode Beta 11.2, but I have the same problem in Xcode 11.1


Thank you!


Mary