can confirm, mine also working now.
also used nGinX, but also played with ports on switch, external I come in via 8124: mapped to 443 on the container that then goes to 8123 on host.
this then locally left 8123 open which then allows me normal http:// onto 8123 via internal address.
I initially misread this and thought I’d need to put my own trusted local subnets in but this I imagine is the internal hassio addressing, notthing to do with your own home subnet(s).
Sorry if this has been answered somewhere else but I thought it may help some confused by the steps earlier in this thread.
Just tried this, but unfortunately this does not work. Access via external URL (I use duckdns) does work, but when connecting via my internal WLAN I still get this certificate error.
Yes the documentation I pasted above is for the NGINX addon. As well as removing the http url and certificate entries, you add the above to configuration.yaml
Once complete, you no longer port forward 443 to 8123 it’s pure 443 external and 8123 internally on http. My reason for implementing this was due to a recent loss of Internet meaning no access to HA internally. Now internal only devices interact with 8123 and mobile apps etc will automatically choose the correct URL based on whether the device is connected to known SSID or not.