JSON-LD Processing Algorithms
        [[JSON-LD-API]], as currently defined, will silently ignore any
        property not defined in a JSON-LD @context. Implementations that
        publish Activity Streams 2.0 documents containing extension
        properties SHOULD provide a @context definition for all extensions.
      </p>

      <p>
        It is also important to note that there are valid JSON constructs which
        cannot be used within a JSON-LD document. For instance, JSON-LD forbids
        "ar