Panel Renderer GameObject has no Panel Settings reference attached after undoing and redoing its creation

Reproduction steps:
1. Create a new project
2. GameObject > UI Toolkit > Panel Renderer
3. Undo and redo Panel Renderer GameObject creation
4. Select Panel Renderer GameObject and observe Panel Settings field in the Inspector

Actual result: Panel Settings reference field is empty
Expected result: Panel Settings reference remains attached

Reproducible with: 6000.0.0f1, 6000.0.79f1, 6000.3.19f1, 6000.5.3f1, 6000.6.0b3, 6000.7.0a2

Reproduced on: macOS Tahoe 26.5 (M4), Windows 11

Notes:

• Issue is only reproducible on the first Panel Renderer GameObject created in the project
• Issue is also reproducible with UI Document GameObject