Happening here too
dcostin-dev
Users receive reputation points by contributing quality content to the forums.
Posts include post and replies published on the forums.
Post authors can mark replies as Accepted to indicate successful solutions.
Apple Developer Forums admins can mark replies as Apple Recommended to indicate an approved solution
Last seen
User for
From
New York, NY, United States
Post
Replies
Boosts
Views
Activity
This seems to be intermittent. Try enough times and it goes through. You need to want it to go through, badly enough, perhaps.
Still there in Xcode 11.7
Clean build folder didn't fix it.
OK, figured it out. It's a Detail view (Master/Detail), and on an iPhone Simulated Metrics (5th panel), Size has to be set to Detail rather than Inferred. If Inferred, for iPhones it's covered by the Master, even though obviously on an iPhone it wouldn't be. Looks like a bug.