Logout Fail with Keycloak and Spring Boot Application

Dear @all :slightly_smiling_face:
I am working with Keycloaks Spring Boot and Spring Security Adapters.

There are two Docker containers - the Keycloak instance (localhost:8080) and a Spring Boot app (localhost:8081). The app uses keycloak for authentication. Unfortunately, I have exactly the same problem as someone earlier has mentioned in this Issue (see: https://issues.redhat.com/browse/KEYCLOAK-16372?jql=key%20%3D%20KEYCLOAK-16372)

Login is possible since the KEYCLOAK.FRONTEND.URL has been set in the docker compose file. But now the Logout ist not possible anymore.

o.k.a.RefreshableKeycloakSecurityContext : failed to invoke remote logout
java.net.ConnectException: Connection refused

I would really appreciate some help since i am working on this for my bachelors thesis
Thank you in advance

Did you find out what the issue was? We are experiencing the same and think that it could be some firewall issue or sth. like that.