The attribute of ItemVisual is absent.

[Anehta]

My colleagues and I consistently encounter an issue where the Visuals attribute of ItemView is frequently lost when we use your ItemVisual. Each time we complete the configuration, merging the code with Plasticscm results in this loss.

[adgray1]

A couple of follow up questions to better understand when this issue appears:

1. Is it only Nova provided (e.g. Button Visuals) visuals types, only custom visual types, or all visual types that are disappearing?
2. When the Visuals disappear, have multiple users modified the same prefabs or scenes where the Visuals are configured?

[Anehta]

A couple of follow up questions to better understand when this issue appears:

1. Is it only Nova provided (e.g. Button Visuals) visuals types, only custom visual types, or all visual types that are disappearing?
2. When the Visuals disappear, have multiple users modified the same prefabs or scenes where the Visuals are configured?

I can confirm that almost all ItemVisual types have disappeared after the merge (but it doesn't trigger this problem 100% of the time).
From the perspective of file comparison, the Prefab actually has not been modified at all.
It's inevitable that multiple people will operate and modify the scene, and this cannot be avoided.

[adgray1]

A couple more questions:

1. Does Unity log any messages to the console when this occurs?
2. If you reimport the scene/prefab with the now-empty ItemVisuals, do the ItemVisuals reappear?

[Anehta]

1. No message
2. Because reimporting takes about thirty minutes, I didn't try it. But I think since restarting Unity can solve some problems, it should be useful.

[adgray1]

Are you saying you tried restarting Unity, and the ItemVisuals have recovered after the restart?

If restarting Unity fixes some things, it's possible simply reimporting could work as well. To clarify your 30 minute reimport time, does reimporting one prefab take 30 minutes or reimporting all assets takes 30 minutes? If the reimport-all is taking 30 minutes, one thing you can try is reimporting just the single prefab with the disappeared ItemVisuals, which should be quite a bit faster.

Right click on a prefab in the Project window and then Reimport:

If reimporting prefabs and/or restarting Unity does resolve the issue, that would confirm the assets aren't corrupted and at least gives you a workaround to recover.

Nova serializes ItemVisuals using Unity's out-of-box [SerializeReference] feature. So if Unity isn't fully reloading [SerializeReference] objects from the merged scenes/prefabs without an explicit restart or reimport, that could explain the disappearing visuals your team is observing. What version of Unity are you using?

[Anehta]

Thanks for reply.
I think this solution is useful.
Version: Unity2021 3.16f

[adgray1]

It may be worth trying to update your project to the latest version of 2021.3 - currently 2021.3.32f1 - as it's possible Unity has fixed the bug in a newer version of the editor. According to Unity's release notes, they have fixed a few SerializeReference/serialization bugs since 2021.3.16f.

[Anehta]

For what it's worth, merging scenes and prefabs in Unity is notoriously unreliable - see this, this, and this for reference, though there are likely quite a few more examples to be found through some additional googling.

If the Visuals are consistently losing configurations in merged scenes (or merged prefabs) and not losing configurations otherwise, then likely however Plastic SCM is merging the scene (or prefab) is resulting in [perhaps unreported] conflicts which corrupt the scene (or prefab) - leading to Unity then being unable to load the Visuals configurations correctly or the Visuals data being deleted entirely.

Does that sound like what you and your team might be observing? If so, there are a few suggestions in the threads linked above describing how teams can try to avoid running into those scene and prefab conflicts/issues.

Hope that helps!
I opened the Prefab that didn't lose the ItemVisual information with vscode and compared it line by line with the local Prefab that lost the ItemVisual information. There wasn't a single byte of difference. So, I suspect that this part of the Serialize Reference is not information within the Prefab.