Here is a plugin to display MIDI messages.
If i am not wrong there was nothing to do that, or i spend my time for nothing . Anyway, that could be useful if you want to route things you don’t know.
Only the last message is displayed, there is no history or what. And it is supposed to display everything, except the system message content.
Here is the repo: https://github.com/vallsv/midi-display.lv2