I finally got the extensions to work by copying them directly into the project, but now there is a further problem:
If I click on a row to open the edit item screen, once I return to the checklist screen that row becomes unclickable and won’t open again until I click on another row first.
(This behavior also exists in the source code files provided.)
This was solved in an earlier chapter by changing the navigationBarTitle, but that doesn’t exist here. How can I make it work properly in this case?