How to reproduce:
1. Open the ‘IN-117004' project
2. Open the ‘Scene’ scene
3. Select the ‘Example’ GameObject in the Hierarchy
4. Observe the result in the Inspector’s script component with a List<T> and Console

Expected result: The icons ‘+' and '-’ are visible and no errors are displayed
Actual result: The icons ‘+' and '-’ are not visible and errors are displayed

Reproducible with: 6000.0.58f1, 6000.2.5f1, 6000.2.6f1
Not reproducible with: 6000.2.4f1, 6000.3.0b3, 6000.4.0a1

Reproducible on: macOS 26.0 (M1 Max)
Not reproducible on: No other environment tested

Note: Console throws out these errors:
- ‘UnityException: GetName can only be called from the main thread’
- ‘NullReferenceException: Object reference not set to an instance of an object'
- ’InvalidOperationException: Operations that change non-concurrent collections must have exclusive access. A concurrent update was performed on this collection and corrupted its state. The collection's state is no longer correct.'