How to reproduce:
1. Open the attached "IN-127716" project
2. Enter Play mode
3. Press the Spacebar button repeatedly
4. Observe the console output

Actual result: Occasionally, the values are incorrect and appear random
Expected result: Values retrieved from FixedList during client-side rollback are correct

Reproducible with: 1.5.0 (6000.5.0a4), 1.10.0 (6000.0.65f1, 6000.3.3f1, 6000.4.0b3, 6000.5.0a4)
Could not test with: 1.2.0 (6000.5.0a4) (compilation errors)

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

Note: It appears that when a FixedList is set up as a GhostField, its values are not always correctly synced to the client during the prediction loop. The reproduction project includes a small sample script in PlayerInventorySystem.cs which adds a new item to a FixedList both on the server and predictively on the client when pressing Space, and then checks its value on the client after the next server tick arrives during the first prediction tick.