NetBird with Keycloak doesn´t work as expected

[melectronics-it]

Describe the problem

When I open the NetBird domain where the login should occur I get a failure message / page:

Oops, something went wrong.
There was an error logging you in.
Error: Unauthenticated

To Reproduce

Steps to reproduce the behavior:

1. Set up Netbird how it is described in the Advanced Guide with Keycloak behind a reverse proxy.
2. Open the Dashboard over the netbird Domain (HTTP-only for testing purposes)
3. The error page is shown instead of the Login page

Expected behavior

See the login page of Keycloak

Are you using NetBird Cloud?

No, self-hosted

NetBird version

0.34.0

NetBird status -dA output:

Not applicable

Do you face any (non-mobile) client issues?

I can´t register any clients.

Screenshots

None

Additional context

None