No MIDI library for Processing 3?

Not sure. I don’t see anything limiting the OS in the properties file that is used by Contributions Manager:

…although that file is from 2015, maybe a setting was added in 3.x that is missing?

Ah: When I uninstall TheMIDIbus it is no longer available for reinstall – I have to re-add it manually from the github download. Then it reappears in contributions manager.

Submitted an issue:

…although I’m not sure the library is actively maintained anymore.