David Mohr • Adobe Employee, Apr 21, 2017Apr 21, 2017
Thank you, Andrew!
Now I understand and see the bug. I've gone ahead and logged a bug against it.
For what it's worth, I also have a work-around. If the last group is not closed and you select the bottom-most layer in that group when you make the change, everything works correctly. Agreed -- not ideal, but something to keep you outta trouble until the fix is ready.