How to reproduce:
1. Create a new Unity project and instal the VFX Graph package
2. Create any VFX Graph and add some properties in the Blackboard
3. Select any of the Properties and click Ctrl + D (Command + D) to duplicate it
4. Observe its position in the Blackboard

Expected results: The new Property appears directly below the original Property, which is a standard behaviour across Unity (e.g. Hierarchy)
Actual results: The new Property appears above all other Properties

Reproducible with: 6000.0.60f1, 6000.2.7f1, 6000.3.0b6, 6000.4.0a2

Reproducible on: macOS Sequoia 15.6 (M1)
Not reproducible on: No other environment tested