core: HomeKit Bridge is totally broken after 2021.8.0 when IPv6 is enabled

The problem

Hello @bdraco!

After update from 2021.7.2 to 2021.8.0 HomeKit Bridge is totally broken. No one device is available. I tried to remove all bridges and delete integration. After adding the main bridge, the devices appear inaccessible. At the same time, TVs in accessory mode cannot added at all - Home app shown error while adding TV. Everything was ok before the update.

Two times after about 15 HA reboot, the devices became available, but in first time after the next reboot, they are unavailable again, in a second time devices became inaccessible right before my eyes, by themselves.

In same time logs are still clean (no errors). HomeKit was configured via UI. iOS latest (14.7.1).

Exposed devices: switch, light, climate, vacuum, sensor, media_player.

What is version of Home Assistant Core has the issue?

2021.8.0

What was the last working version of Home Assistant Core?

2021.7.2

What type of installation are you running?

Home Assistant Container

Integration causing the issue

homekit

Link to integration documentation on our website

https://www.home-assistant.io/integrations/homekit/

Example YAML snippet

Configuration.yaml:

# Configure a default setup of Home Assistant (frontend, api, etc)
#default_config:

# Base components
#cloud:
config:
counter:
dhcp:
#energy:
frontend:
  themes: !include_dir_merge_named themes
#history:
http:
  ssl_certificate: /certs/fullchain.pem
  ssl_key: /certs/privkey.pem
homeassistant:
  customize: !include customize.yaml
image:
input_boolean:
input_datetime:
input_number:
input_select:
input_text:
#logbook:
logger:
  default: error
  logs:
    pychromecast.socket_client: fatal
    custom_components.r4s_kettler: fatal
#map:
media_source:
mobile_app:
my:
person:
ssdp:
sun:
system_health:
tag:
timer:
updater:
zeroconf:
#zone:

# Includes
group: !include groups.yaml
automation: !include automations.yaml
script: !include scripts.yaml
scene: !include scenes.yaml
binary_sensor: !include binary_sensors.yaml
sensor: !include sensors.yaml
switch: !include switches.yaml
light: !include lights.yaml
media_player: !include media_players.yaml
climate: !include climates.yaml
camera: !include cameras.yaml
rest_command: !include rest_commands.yaml
panel_iframe: !include panel_iframes.yaml
vacuum: !include vacuums.yaml
tts: !include tts.yaml

....

Anything in the logs that might be useful for us?

No response

Additional information

No response