My app went blank (I believe it hasn’t saved any of the changes I made) and when I try to open it I get the message " Not saved. It looks like this app is open in another tab. Do you want to take over here?" (I have no other tabs open).
The error should go away now, but you’ll have to reconfigure that detail screen, unfortunately. If you have any idea how you got into that state, or if you manage to get into that state again, please let me know.