This issue is introduced by PR #1338 (see ) that introduces tab navigation in the metadata property sheet. Its cause is that the library angular-chosen does not yet support the events ng-blur which would be required to switch of the edit mode when losing the keyboard focus.
Steps to reproduce:
1. Open "Add Event"
2. Use "Tab" to navigate through the fields
When a selection field (containing a selection dropdown list) loses the keyboard focus, it is still in the edit mode.
When a selection field loses the keyboard focus, the edit mode should be disabled.
Workaround (if any):
Just ignore it - it works.