Think about removing a default Envelope from `embedded-editor`

When the PMML Editor, will it be added to the default Envelope in `embedded-editor`? If so, this will make the Envelope be bigger than it has to be, so I think every channel should declare its own Envelope application. Potentially, we should also inclusive separate Envelopes for separate Editors on the same channel. This task is to think about that and discuss what's the best approach.