Hi,
Is it possible to filter traffic to and from the container network?
You can try to use zone policy firewall + set correct name of the bridge interface but need to test it.
I will test some stuff. I just noticed the interface isn’t shown when doing ‘show int’.
Seems like the container stuff has some rough edges 
Use “ip link show”
As podman bridges is not regular VyOS interfaces
Maybe we should to add them to the output