<PackageReference Include="Newtonsoft.Json" Version="13.0.3" />

ExtensionDataSetter

public sealed delegate ExtensionDataSetter : MulticastDelegate
Sets extension data for an object during deserialization.
using System.Runtime.CompilerServices; namespace Newtonsoft.Json.Serialization { } namespace Newtonsoft.Json.Serialization { public delegate void ExtensionDataSetter (object o, string key, [System.Runtime.CompilerServices.Nullable(2)] object value); }