Server connection lost, reconnecting message

I have a fresh install of HA with Node-Red plugin. I have SSL enabled through Duckdns plugin. When I access Node-Red in HA everything is fine. When I access Node-Red directly on port 1880 I get constantly “Server connection lost, reconnecting in…” in message banners. Although it appears to work and I get no errors in log messages.

Any ideas ?

Config:

credential_secret: '!secret passwd'
dark_mode: false
http_node:
  username: '!secret user'
  password: '!secret passwd'
http_static:
  username: '!secret user'
  password: '!secret passwd'
ssl: true
certfile: fullchain.pem
keyfile: privkey.pem
require_ssl: true
system_packages: []
npm_packages: []
init_commands: []

Version info:

System Health

Home Assistant Core Integration

version: 0.118.4
installation_type: Home Assistant OS
dev: false
hassio: true
docker: true
virtualenv: false
python_version: 3.8.6
os_name: Linux
os_version: 4.19.127-v7
arch: armv7l
timezone: UTC

Home Assistant Cloud

logged_in: false
can_reach_cert_server: ok
can_reach_cloud_auth: ok
can_reach_cloud: ok

host_os: HassOS 4.16
update_channel: stable
supervisor_version: 2020.12.2
docker_version: 19.03.12
disk_total: 28.6 GB
disk_used: 2.1 GB
healthy: true
supported: true
board: rpi3
supervisor_api: ok
version_api: ok
installed_addons: Duck DNS (1.12.4), File editor (5.2.0), Samba share (9.3.0), Node-RED (7.2.11)

Lovelace

dashboards: 1
mode: auto-gen
resources: 0

Did you ever solve this? I have the same problem.