"EndLayoutGroup: BeginLayoutGroup must be called first." error when selecting "Reset", "Sample Bind-Pose" or "Enforce T-pose" in the Humanoid Avatar Configuration

Steps to reproduce:

1. Create a new project using Universal 3D template
2. Import the attached "model.fbx" and select it in Project window
3. In the Inspector, navigate to the "Rig" tab
4. Set the Animation Type to "Humanoid" and click "Apply"
5. Click on the "Configure..." button
6. Scroll down and click on the "Pose" dropdown
7. Select any option - "Reset", "Sample Bind-Pose" or "Enforce T-pose"
8. Click "Apply"
9. Observe the Console

Actual results: "EndLayoutGroup: BeginLayoutGroup must be called first." each time an option is selected and "Apply" is clicked

Expected results: No errors

 

Reproducible with versions: 2023.1.0a4, 6000.0.71f1, 6000.3.12f1, 6000.4.1f1, 6000.5.0b1, 6000.6.0a1

Tested on (OS): Ubuntu 24.04 (reproducible), macOS 26.3 (not reproducible)