I am trying to serialize an object with a static System.Version field:
[JsonObject(MemberSerialization.OptIn)]
public class MyObj
{
[JsonPro
ItemConverterType allows you to specify a converter to use for collection items. See Proper way of using Newtonsoft Json ItemConverterType. Since string and Version aren't treated as collections, it's ignored. For a converter on the property itself use [JsonConverter].
Conversely, if you had a static List it would be appropriate to use [JsonProperty(ItemConverterType = typeof(VersionConverter))].