Dear Maintainer, lyrebird, the successor of obfs4proxy, has already been accepted into debian (testing) repository recently. If lyrebird is added to /etc/apparmor.d/abstractions/tor like obfs4proxy (and /usr/bin/snowflake- client), tor can use lyrebird as a pluggable transport.
In tor package version 0.4.9.14-1: $ grep lyrebird /etc/apparmor.d/abstractions/tor /usr/bin/lyrebird Pix, So the lyrebird entry has been added. Closing.