Host/Network 'accurate' not found when trying to enable firewall

[kb-elmo]

There seems to be a mismatch between the command that Firehol tries to run and the way that IPtables interprets the command.

ERROR   : # 1.
WHAT    : A runtime command failed to execute (returned error 2).
SOURCE  : 30@/etc/firehol/firehol.conf: server:
COMMAND : /sbin/iptables -t filter -A in_public4 -s accurate -m conntrack --ctstate NEW\,ESTABLISHED -j ACCEPT
OUTPUT  :

iptables v1.6.0: host/network `accurate' not found
Try `iptables -h' or 'iptables --help' for more information.

This error occurs 12 times in a row when running firehol nofast save.

When changing the firehol ruleset mode in firehol-defaults.conf to 'optimal' the error changes accordingly.

OS is Debian 9.13 Stretch
Firehol version is 3.1.1

[kb-elmo]

Any ideas on this?

Or is firehol just not working anymore with certain IPtables versions now?