Hi. I’m experiencing a similar issue after the upgrade to HA Core 2021.7 (on raspbian OS).
Integration: HTTP (documentation, issues)
First occurred: 10:51:04 (771 occurrences)
Last logged: 13:23:36
A request from a reverse proxy was received from 172.17.0.2, but your HTTP integration is not set-up for reverse proxies; This request will be blocked in Home Assistant 2021.7 unless you configure your HTTP integration to allow this header`.
Only recently (less than one month ago) I switched from a simple SSL way to secure HA to Caddy on docker (on the same machine).
Also, that message appears in concidence with the disconnection and reconnection of one of my smart plugs.
So, should I edit the configuration.yaml too?
Is it correct to add the following code?