for unattended upgrades

Maybe explain how to change /etc/apt/apt.conf.d/50unattended-upgrades too to get the latest Tor (or whatever else is needed) too?

At a stable Debian image here Tor stayed at 0.4.3.5 (from the Debian repository) although the Tor repository contained 0.4.4.6.

FWFW /etc/apt/sources.list contains:

        "origin=Debian,codename=${distro_codename}";
        "origin=TorProject";
};

but that seems not to be sufficient to upgrade Tor when 0.4.4.6 when it appeared in the Tor repository.