in order to prevent the popover on the right and the master pane on the left. I couldn’t get both popovers to display before or after adding the code on page 1063-1064. Fairly specific question but: is this something that is no longer able to happen in a later version of Xcode? Does split view controller auto-prevent you from having more than one popover at a time?
The issue with more than one popup displaying at the same time was present with the beta version of iOS 11 that I was working with when the book was written. But as you mention, that seems to no longer happen with iOS 11.2 since I can’t reproduce this issue now either. So you do not have to implement the UISplitViewControllerDelegate as per pages 1063 and 1064 and your app would work fine