I’ve recreated this in a blank project:
- Create a new widget.
- Create Horizontal Box and nest two other engine widgets inside.
- set Horizontal Box to become variable and give it a name X.
- Compile and Save.
- Now find X in hierarchy or on designer panel, right click, and replace with Vertical Box from the drop down menu.
- Set that new Vertical Box to become variable and give it the same name X.
- Unreal will freeze and crash by self, will trigger breakpoint and crash in Visual Studio.
This works with Vertical to Horizontal Box as well. Haven’t tried other combinations.