How to reproduce:
1. Open the attached project “IN-128377”
2. Next to the play modes (next to play button, should be saying “default”) press arrow pointing down
3. Select “Configure Play Mode Scenarios”
4. In Play Mode Scenarios window, press + sign and create a new scenario

Actual result: 
No scenarios are visible even after creating a new one
Expected result: After creating a new scenario, it stays and is playable

Reproducible with: 2.0.0-pre.1 (6000.3.6f1), 2.0.1 (6000.3.0a3, 6000.3.6f1)
Not reproducible with: 1.6.3 (6000.0.65f1, 6000.3.0a3, 6000.3.6f1), 2.0.1 (6000.4.0a1, 6000.4.0b7, 6000.5.0a6)

Reproducible on: macOS 26.1 (M1 Pro)
Not reproducible on: No other environment tested

Notes:
- I was not able to reproduce it on an empty project
- User mentioned that this issue happened after upgrading from 6000.2 to 6000.3 (I was not able to reproduce this)