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Container macvlan accepts IPv6 RA but IPv6 address not visible from the host

When using macvlan interfaces with containers the container is able to accept IPv6 RA and gets an IPv6 IP address form the connected router.
This IPv6 address is globally routable and can be used by the container for internet connectivity both incoming and outgoing traffic.

How is it possible from outside the container (from the host) to list what the IPv6 address of the containers is? This is not visible via the inspect command of the container or the network.

Steps to reproduce the behavior
1- Provision IPv6 addresses
2- install docker
3- attempt to make a ipv6 aware network
4- attempt to ping ipv6 only space.

Output of docker version:

Client: Docker Engine - Community
Version: 19.03.8
API version: 1.40
Go version: go1.12.17
Git commit: afacb8b7f0
Built: Wed Mar 11 01:25:46 2020
OS/Arch: linux/amd64
Experimental: false

Server: Docker Engine - Community
Engine:
Version: 19.03.8
API version: 1.40 (minimum version 1.12)
Go version: go1.12.17
Git commit: afacb8b7f0
Built: Wed Mar 11 01:24:19 2020
OS/Arch: linux/amd64
Experimental: false
containerd:
Version: 1.2.13
GitCommit: 7ad184331fa3e55e52b890ea95e65ba581ae3429
runc:
Version: 1.0.0-rc10
GitCommit: dc9208a3303feef5b3839f4323d9beb36df0a9dd
docker-init:
Version: 0.18.0
GitCommit: fec3683

Output of docker info:

Client:
Debug Mode: false

Server:
Containers: 22
Running: 22
Paused: 0
Stopped: 0
Images: 121
Server Version: 19.03.8
Storage Driver: overlay2
Backing Filesystem:
Supports d_type: true
Native Overlay Diff: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
Volume: local
Network: bridge host ipvlan macvlan null overlay
Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
Swarm: inactive
Runtimes: nvidia runc
Default Runtime: runc
Init Binary: docker-init
containerd version: 7ad184331fa3e55e52b890ea95e65ba581ae3429
runc version: dc9208a3303feef5b3839f4323d9beb36df0a9dd
init version: fec3683
Security Options:
apparmor
seccomp
Profile: default
Kernel Version: 5.1.21-050121-generic
Operating System: Ubuntu 18.04.4 LTS
OSType: linux
Architecture: x86_64
CPUs: 16
Total Memory: 62.81GiB
Name: systemdnet
ID: V7ZF:SDIY:SLQS:7SAK:TAMH:G77I:ZNBS:XQBB:YGVR:EUJD:VP2X:2UJN
Docker Root Dir: /var/lib/docker
Debug Mode: false
Registry: https://index.docker.io/v1/
Labels:
Experimental: false
Insecure Registries:
127.0.0.0/8
Live Restore Enabled: false

Additional environment details (AWS, VirtualBox, physical, etc.)
Reproduced on two seperate dedicated server hosts, though both were of similar host operating systems (ubuntu and debian).

I can reproduce this on a hetzner vps, and can send the login details to a dev if needed. No confidential material exists on the vps and they provision their vps’s with a /64 ipv6 space.