Mixing ECS Fargate IPV6 and Network Load Balancers

Is it possible to create an ECS service on Fargate with an IPV6 IP address and attach a network load balancer to the service? If I setup an ECS service on Fargate on an IPV6 subnet then the tasks it creates correctly have an IPV6 IP address assigned to them. However, if I use the same configuration for the service but add a network load balancer then the tasks created no longer have IPV6 IP addresses assigned to them. This occurs whether the target group has an IPV6 target or an IPV4 target.