Serialization of interfaced fields

    [JsonObject(MemberSerialization.OptIn)]
    public interface INode {
    }

    [JsonObject(MemberSerialization.OptIn)]
    public class BinaryTree : INode {
        [JsonProperty]
        public INode left;

    [JsonProperty]
    public INode right;
    }

    [JsonObject(MemberSerialization.OptIn)]
    public class LeafNode1 : INode {
        [JsonProperty]
        public int A;
    }

    [JsonObject(MemberSerialization.OptIn)]
    public class LeafNode2 : INode {
        [JsonProperty]
        public bool B;
    }

    [JsonObject(MemberSerialization.OptIn)]
    public class InterfaceDemoBehavior : BaseBehavior {
        [JsonProperty]
        public INode MyTree;
    }