KeyNotFoundException error thrown in the Console when clicking on a button in a UIDocument

Reproduction steps:
1. Open the attached "ReproProj" project
2. Click on the “Load scenario maps” button to the left of the Play mode button
3. Click the “Edit map Test.Scenario” button
4. In the Game view, click on the “Triggers” button
5. Observe the Console logs

Expected Result: KeyNotFoundException error thrown in the Console
Actual Result: No errors thrown in the Console

Reproducible with: 6000.0.5f1
Could not test with: 2021.3.39f1, 2022.3.32f1 (due to errors when downgrading)

Reproducible on: Windows 11 Pro
Not reproducible on: No other environments tested

Notes:

• The error is continuously thrown even after leaving the Play mode
• Full error message: “KeyNotFoundException: The given key 'ObservableValue: True' was not present in the dictionary.”