Bugfix
SecurityStructure:SecurityStructure.Root and SecurityStructure:Root should not inherit from tl.element:StructuredElement.
Because StructuredElement is abstract and does not provide a storage specification for the "parent" reference, instances (singletons) of the type SecurityStructure:Root cannot be edited at all ("Invalid storage implementation for attribute 'tl.element:StructuredElement#parent'.").
This singleton or better "well known instance" does not have to be a StructuredElement.
Migration
The necessary (relatively complicated) data migration happens automatically: The singleton object SecurityStructure#ROOT moves to the GenericObject table. Its (actually nonsensical) name attribute becomes a Flex attribute.
Test
- /com.top_logic.demo/src/test/java/test/com/top_logic/demo/scripted/model/TestSecurityStructureEdit.script.xml