Class ThreadEventDataAbstract

Whether this is an original message or an acknowledgement

Additional data to send

If present, then an error occurred in another context, and it needs to be handled

Event GUID used to look up event promises to resolve

If set, this data will be transferred between threads, instead of copied. For more info see https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API/Transferable_objects