At the bottom of rkhunter.conf (I also tried placing it separately in rkhunter.conf.local), and after checking for invisible chars,
Unknown configuration file option: CRON_DAILY_RUN="false"
Unknown configuration file option: CRON_DB_UPDATE="true"
Unknown configuration file option: APT_AUTOGEN="true"
Comes up for
rkhunter -C. rkhunter is Version 1.4.6-5 from Maintainer: Debian Security Tools on Debian 10.1.
I already tried purging and reinstalling. Inserting other options in rkhunter.conf.local, such as
ALLOW_SSH_ROOT_USER = yes, does not trigger a warning. Only these three give issues.
PS: I say rkhunter.conf.local but it doesn't matter, the result is the same if I edit rkhunter.conf directly.