I can confirm that since I updated from Ubuntu 18.04 (Chromium deb) to Ubuntu 20.04 (Chromium snap), I can no longer connect to my device using WebMIDI (nor WebUSB).
For information, the web app asks permission to "Use your MIDI devices", but the call to "navigator.requestMIDIAccess()" fails. In /var/log/syslog I get the same log entries as in the previous post: chromium_chromium.desktop[11556]: ALSA lib conf.c:3916:(snd_config_update_r) Cannot access file /usr/share/alsa/alsa.conf chromium_chromium.desktop[11556]: ALSA lib seq.c:935:(snd_seq_open_noupdate) Unknown SEQ hw -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1854676 Title: [snap] Web Midi API doesn't work To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/chromium-browser/+bug/1854676/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs