Crash when removing/adding element in nested serialized list of prefab instance

[Ivan]

Unity v5.5.0f3 is crashing when removing or adding an element in a nested list on a prefab instance.

Steps to Repro

Define the following classes:

public abstract class BaseEvent {}
public class MessageEvent : BaseEvent {
    public string[] messages;
}
public class EventManager : SerializedMonoBehaviour {
    [OdinSerialize]
    private List<BaseEvent> events;
}

1. Create an empty GameObject with an EventManager. Add a MessageEvent to the events list and a single string to the messages array.
2. Save the GameObject as a prefab.
3. Select the original GameObject instance (not the prefab).
4. Delete the inner message (or click the plus to add a new element to the array).
5. Observe crash.
6. (Possibly relevant side effect:) Upon reopening Unity, the GameObject is no longer an instance of the prefab.

[Tor Esa Vestergaard]

Thank you for the report! We've reproduced this issue and are investigating it promptly.

[Tor Esa Vestergaard]

We've found the bug and fixed it in the next patch (0.9.0.2), which should hopefully be distributed sometime today.

Edit: Meanwhile, you can use a List<string> to contain your messages, as the error was related to prefab modifications that changed the length of an array.

[Tor Esa Vestergaard]

Removing version: 0.9.0.0 (automated comment)