400 Bad Request, Item-Channel linking; running behind reverse proxy

Hi all,

i’m running an openHab (5.1.0; Problem existed on earlier release as well) instance on docker behind an Traeffik Reverse Proxy. Everythink is running fine. Except for linking channel to items, trying this i get an 400 Response from the API. This doesn’t happen when ich access the openHab instance directly via IP.

Other PUT operations (e.g. creation of items) are working when behind the reverse proxy.

Anyone has an idea what could be wrong here?

Thanks and BR Chris