Can't run example from Colyseus Unity SDK, got JsonSerializationException

Hi, there's an issue, need guys to help!

platform: WebGL
There has no exception when running in Unity Editor, but has an exception in the browser.

When the client joins the room, the exception shows up:

JsonSerializationException: Unable to deserialize instance of 'Colyseus.Schema.MapSchema`1[[System.String, mscorlib, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089]]' because there is no parameterless constructor is defined on type.
  at GameDevWare.Serialization.Metadata.TypeDescription.CreateInstance () [0x00000] in <00000000000000000000000000000000>:0 
Rethrow as SerializationException: Failed to read value for member 'attributes' of 'ExampleNetworkedUser' type.
More detailed information in inner exception.
  at GameDevWare.Serialization.Serializers.ObjectSerializer.DeserializeMembers (GameDevWare.Serialization.IJsonReader reader, GameDevWare.Serialization.IndexedDictionary`2[KeyT,ValueT] container, GameDevWare.Serialization.Serializers.ObjectSerializer& serializerOverride) [0x00000] in <00000000000000000000000000000000>:0 
--- End of stack trace from previous location where exception was thrown ---
  at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x00000] in <00000000000000000000000000000000>:0

The Unity SDK updates frequently lately.

  1. download the sdk:
  2. download the example:
  3. copy Example~ folder to unity and remove the "~"
  4. build and run to see if all right.
    Good luck!