It could be useful to allow an nft rule to be created from raw nftables syntax.. This would allow for complex configurations for users while they await native implementation of nftables syntax.

Configuration could look something like:

set firewall ipv4 forward filter rule 10 action nft-rule
set firewall ipv4 forward filter rule 10 nft-rule "ct state vmap { established : accept, related : accept, invalid : drop }"