Reproduction steps:
1. Open attached "NUP43" Unity project.
2. Open "1" scene.
3. Drag and drop "2" scene into the "1" scene hierarchy.
4. Expand both scenes in the hierarchy.
5. Click on "GameObject" game object and add "Cube" reference to the "Refr" script "Target" variable.
6. Play the scene.

Actual behavior: "Cube" game object duplicates to the "1" scene(GIF attached).
Expected behavior: only one "Cube" game object stays in both scenes.