overwrite the directory /mattermost/client/images/favicon in the container; mapped it to a custom directory on host using the volumes option in the docker-compose.yml file:
volumes:
- ${MATTERMOST_CONFIG_PATH}:/mattermost/config:rw
[...]
- /path/to/new/favicon-files:/mattermost/client/images/favicon:ro
but the favicon is not updated, changes in yml are not reflected