Does anyone here use Solus as a platform when building snaps?
I ran into some problems before I could start,
it's multipass and some firewall settings I guess.

$ multipass launch                                                   
launch failed: Failed to set iptables rule for table mangle: iptables: No chain/target/match by that name.

Any thoughts?

I'm able to run multipass on manjaro and on manjaro the output of
sudo iptables -S
is

-P INPUT ACCEPT
-P FORWARD ACCEPT
-P OUTPUT ACCEPT
-A INPUT -i mpqemubr0 -p tcp -m tcp --dport 53 -m comment --comment "generated for Multipass network mpqemubr0" -j ACCEPT
-A INPUT -i mpqemubr0 -p udp -m udp --dport 53 -m comment --comment "generated for Multipass network mpqemubr0" -j ACCEPT
-A INPUT -i mpqemubr0 -p udp -m udp --dport 67 -m comment --comment "generated for Multipass network mpqemubr0" -j ACCEPT
-A FORWARD -i mpqemubr0 -o mpqemubr0 -m comment --comment "generated for Multipass network mpqemubr0" -j ACCEPT
-A FORWARD -s 10.94.23.0/24 -i mpqemubr0 -m comment --comment "generated for Multipass network mpqemubr0" -j ACCEPT
-A FORWARD -d 10.94.23.0/24 -o mpqemubr0 -m conntrack --ctstate RELATED,ESTABLISHED -m comment --comment "generated for Multipass network mpqemubr0" -j ACCEPT
-A FORWARD -i mpqemubr0 -m comment --comment "generated for Multipass network mpqemubr0" -j REJECT --reject-with icmp-port-unreachable
-A FORWARD -o mpqemubr0 -m comment --comment "generated for Multipass network mpqemubr0" -j REJECT --reject-with icmp-port-unreachable
-A OUTPUT -o mpqemubr0 -p tcp -m tcp --sport 53 -m comment --comment "generated for Multipass network mpqemubr0" -j ACCEPT
-A OUTPUT -o mpqemubr0 -p udp -m udp --sport 53 -m comment --comment "generated for Multipass network mpqemubr0" -j ACCEPT
-A OUTPUT -o mpqemubr0 -p udp -m udp --sport 67 -m comment --comment "generated for Multipass network mpqemubr0" -j ACCEPT

while on solus

-P INPUT ACCEPT
-P FORWARD ACCEPT
-P OUTPUT ACCEPT
-A INPUT -i mpqemubr0 -p tcp -m tcp --dport 53 -m comment --comment "generated for Multipass network mpqemubr0" -j ACCEPT
-A INPUT -i mpqemubr0 -p udp -m udp --dport 53 -m comment --comment "generated for Multipass network mpqemubr0" -j ACCEPT
-A INPUT -i mpqemubr0 -p udp -m udp --dport 67 -m comment --comment "generated for Multipass network mpqemubr0" -j ACCEPT
-A OUTPUT -o mpqemubr0 -p tcp -m tcp --sport 53 -m comment --comment "generated for Multipass network mpqemubr0" -j ACCEPT
-A OUTPUT -o mpqemubr0 -p udp -m udp --sport 53 -m comment --comment "generated for Multipass network mpqemubr0" -j ACCEPT
-A OUTPUT -o mpqemubr0 -p udp -m udp --sport 67 -m comment --comment "generated for Multipass network mpqemubr0" -j ACCEPT
3 months later

onemoz but the extra steps provided doesn't really work for me.

I was not able to get it working either, so I had to revert back to Manjaro.
Hopefully this will be picked up by the Solus devs.