Pipewire prevents midi devices to by opened by other apps (Reaper)
Lastest Manjaro update has introduced a dependency with Pipewire when installing KDE. Opening Reaper (with Alsa as its audio backend) shows the following message: ALSA lib rawmidi_hw.c:235: (snd_rawmidi_hw_open) open /dev/snd/midiC3D0 failed: Device or resource busy cannot open port "hw:3,0,0": Device or resource busy.
As you can see Reaper cannot access midi devices such as keyboards when this happens.
Stoping Pipewire and restarting Reaper makes it work as expected: systemctl --user stop pipewire.socket systemctl --user stop pipewire.service
Using Jack + a2jmidid seems to work fine, though.