What is the prefab is not valid since it has no root game object error?

Hey everyone,

I would love to know what causes this error and how I can fix it. There isn’t a single post related to this anywhere on the web… How is this even possible?,There is literally not a single report of this on the entire web? Can someone please tell me what causes it and how I can fix it.

I’ve since managed to fix the issue by first creating an empty prefab and replacing it afterwards. Still not entirely sure, what was causing the issue, but it has been solved.