I’ve tested this in v5.5.3 and it seems to behave correctly:
Tested it 3 way:
- setting struct data for the dragged widget
- for the visual
- for the custom OP itself
All 3 get delivered onDrop. Restart the project → still the same. Nothing shifts or fails to pass the data.
Consider applying engine hot-fixes. If that does not help, you may need to recreate the widget from scratch.