Workaround, based on Michael's comment and guidance over IRC:
1) install the unity8-session snap
2) remove the unity8-session-snap debian package, if you have it installed
3) if you have already some unity8 apps installed as a snap, connect their "mir" interface manually
Workaround, based on Michael's comment and guidance over IRC:
1) install the unity8-session snap
2) remove the unity8-session-snap debian package, if you have it installed
3) if you have already some unity8 apps installed as a snap, connect their "mir" interface manually