Refactor: a class can be moved to outter scope but CANNOT be moved to inner scope Follow

As a result, this refactor cannot be reversed.

Does any body have the same problem?

Here, "move to outter scope" is means:

FROM:

    public class Class3
    {
        public class Class3Inner
        {
           
        }
    }
TO:

    public class Class3
    {
    }
    public class Class3Inner
    {
    }