nifi docker volume persistence

docker-compose.yml

version: "3"
services:
  zookeeper:  # the configuration manager
      hostname: zookeeper
      container_name: zookeeper
      image: 'bitnami/zookeeper:3.6.1'
      environment:
        - ALLOW_ANONYMOUS_LOGIN=yes
  nifi:
    image: apache/nifi:1.11.4
    ports:
      - 8080:8080 # Unsecured HTTP Web Port
    environment:
      - NIFI_WEB_HTTP_PORT=8080
      - NIFI_CLUSTER_IS_NODE=true
      - NIFI_CLUSTER_NODE_PROTOCOL_PORT=8082
      - NIFI_ZK_CONNECT_STRING=zookeeper:2181
      - NIFI_ELECTION_MAX_WAIT=1 min
    links:
      - registry
    volumes:
      - ./for_nifi/state:/opt/nifi/nifi-current/state
      # - ./for_nifi/conf:/opt/nifi/nifi-current/conf
      - ./for_nifi/db:/opt/nifi/nifi-current/database_repository
      - ./for_nifi/flowfile:/opt/nifi/nifi-current/flowfile_repository
      - ./for_nifi/content:/opt/nifi/nifi-current/content_repository
      - ./for_nifi/provenance:/opt/nifi/nifi-current/provenance_repository
      - ./for_nifi/logs:/opt/nifi/nifi-current/logs
  registry:
    hostname: registry
    #image: apache/nifi-registry:0.6.0
    # https://github.com/michalklempa/docker-nifi-registry/blob/1cc1970b480c9568d1b5691359cac070ac51b257/docker-compose.github.yml
    image: michalklempa/nifi-registry:0.6.0-default
    container_name: registry
    environment:
      #DEBUG: 1
      FLOW_PROVIDER: git
      #GIT_REMOTE_URL: git@github.com:michalklempa/docker-nifi-registry-example-flow.git
      #GIT_CHECKOUT_BRANCH: example
      FLOW_PROVIDER_GIT_FLOW_STORAGE_DIRECTORY: /opt/nifi-registry/flow-storage-git
      #FLOW_PROVIDER_GIT_REMOTE_TO_PUSH: origin
      #GIT_CONFIG_USER_NAME: 'Michal Klempa'
      #GIT_CONFIG_USER_EMAIL: michal.klempa@gmail.com
    volumes:
      - ./for_registry/registry/:/opt/registry:ro
      - ./extensions:/opt/nifi/nifi-current/extensions
      - ./flow_storage:/opt/nifi-registry/flow-storage-git
      #- ./conf_nifi-registry/providers.xml:/opt/nifi-registry/nifi-registry-0.6.0/conf/providers.xml
    ports:
      - 18080:18080

How can I persist the state & especially configuration of my nifi flows outside a docker container? When trying to do so https://gist.github.com/geoHeil/42e213e8532623181cc5fbb65a30981c I fail to persist the configuration. - ./for_nifi/conf:/opt/nifi/nifi-current/conf when trying to map the conf directory like this - NiFi will no longer start up. I also noticed, that no changes of i.e. controller settings seem to be reflected in the conf directory. Hoever 1) my current flow and 2) any configuration clicked in the UI i.e. the link in the controller settings to the registry are lost when restarting the container.

Hopefully some replies here https://apachenifi.slack.com/archives/C0L9VCD47/p1591634722155500 or here ;)