iptables warnings

[53d117460ec63d70]

firewalld is logging the following warnings when installing UCP 3.3.3 using launchpad:

Nov 26 08:54:16 myvm firewalld[9577]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w10 -t filter -F DOCKER' failed: iptables: No chain/target/match by that name.
Nov 26 08:54:16 myvm firewalld[9577]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w10 -t filter -X DOCKER' failed: iptables: No chain/target/match by that name.
Nov 26 08:54:16 myvm firewalld[9577]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w10 -t filter -F DOCKER-ISOLATION-STAGE-1' failed: iptables: No chain/target/match by that name.
Nov 26 08:54:16 myvm firewalld[9577]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w10 -t filter -X DOCKER-ISOLATION-STAGE-1' failed: iptables: No chain/target/match by that name.
Nov 26 08:54:16 myvm firewalld[9577]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w10 -t filter -F DOCKER-ISOLATION-STAGE-2' failed: iptables: No chain/target/match by that name.
Nov 26 08:54:16 myvm firewalld[9577]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w10 -t filter -X DOCKER-ISOLATION-STAGE-2' failed: iptables: No chain/target/match by that name.
Nov 26 08:54:16 myvm firewalld[9577]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w10 -t filter -F DOCKER-ISOLATION' failed: iptables: No chain/target/match by that name.
Nov 26 08:54:16 myvm firewalld[9577]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w10 -t filter -X DOCKER-ISOLATION' failed: iptables: No chain/target/match by that name.
Nov 26 08:54:16 myvm firewalld[9577]: WARNING: COMMAND_FAILED: '/usr/sbin/iptables -w10 -D FORWARD -i docker0 -o docker0 -j DROP' failed: iptables: Bad rule (does a matching rule exist in that chain?).

Can these warnings be safely ignored?

$ launchpad version
version: 1.1.0-rc4
commit: 301a9cc

Thanks.