The documentation says
Messages have a string message parameter that is used as way to address messages. The Subscribe and Send methods use generic parameters to further control how messages are delivered - two messages with the same message text but different generic type arguments will not be delivered to the same subscriber.
but it doesn't say anything about what is the role of the subscriber. I've just found in my testing that if I have the same generic parameters, but a different subscriber than sender, I won't receive the message. What are the exact rules for receiving a message?
I'm also not sure if there's a way to either catch all messages, or just somehow debug the send messages to see which ones aren't being delivered to anyone?