Entity screen binding gone (entity details screen) by Ales Potocnik Hahonina

When you create a new screen (detail screen in my case) you can tick a check box to specify if it's used as default. From what I can see this is then stored as EntityType.Attributes -> DefaultScreen node in ApplicationDefinition.Isml. I had an issue with this binding being gone all of a sudden when I changed something on the detail screen which may have caused the screen to become invalid (run time error). When I ran the LightSwitch application it would show the stock detail screen instead of the custom one. When I removed possibly offending changes it would no longer show the custom detail screen.

Luckily I had a backup of entire application and when I compared the .Isml files I noticed that above mentioned node was missing. Manually copy-pasting the node from a backup fixed the binding issue.

Not sure if this is intended behaviour - if you mess up the screen, show the default but I would much prefer to see a run time error, especially when running in debug mode. And certainly the binding should not be changed quietly.