No connection after updating to Home Assistant 2026.6.0

[trmpluym]

iOS device model, version and app version

Model Name: iPad Air 2
Software Version: 15.8.8
App version: [2026.5.0]

Home Assistant Core Version
2026.6.0

Describe the bug
Cannot connect anymore

To Reproduce
Open the companion app.

Expected behavior
a working companion app.

Screenshots

Additional context
Re-installed the app, re-entered the connection info and cleared the Safari cache, still no connection.

[tuky1988]

I have the same problem, tried with http Internal URL ánd with Nabu Casa External URL - same result.

[bgoncal]

How does it behaves when you open the same URLs in Safari?

[trmpluym]

It shows a screen where I only can choose to open the companion app..

[trmpluym]

Also tried Chrome, same screen but without de Home Assistant App banner.

[bgoncal]

So it't not only in the companion app that is not working, it's a general issue with your Home Assistant installation after upgrading to 2026.6.0.

This is either frontend or core related, I will transfer it to frontend first

[jpbede]

Could you please check your logs and see if there is anything related in there? Or attach it here, if possible

[trmpluym]

In HA I cannot find related items. In the iPad I found:

[jpbede]

Could you please give some informations how your HA is installed? Are you using HAOS?
Is HA available through its internal address? Do you have reverse proxy like NGINX in front of HA as you're using duckdns?

What is http://<ip address of HA>:4357/ showing?

[trmpluym]

I use HAOS using split DNS. Internal i use https:\hostname.duckdns.org:8123 external i use https:\hostname.duckdns.org. No reverse proxy. I also tried using my internal IP address. https:\192.168.1.20:8123. On my iPhone the Companion APP works without problems with the same settings.

http:\192.168.1.20:4357 shows:

Home Assistant observer
Supervisor: Connected
Support: Supported
Health: Healthy

[jpbede]

When using port 8123 (which is HA) you need plain HTTP not HTTPS, e.g. http://192.168.1.20:8123 not https://192.168.1.20:8123, except you've configured HA to use SSL certificate. So you can you reach http://192.168.1.20:8123 from other devices?

When you say, your using https://hostname.duckdns.org externally, you need something that accepts the connection and does the SSL. What apps do you have in HAOS?

[jpbede]

Could you maybe also share your http config?

[agentthumb]

I have the same issue since updating to 2026.6. Also running iOS 15.8.8.

Both the browser and companion app stopped loading.

Was working fine on 2026.5.4.