After installing plugin, Logstash cannot be viewed from Kibana

[luckb008]

This is a Dockerfile:

FROM logstash:5.3.0

RUN logstash-plugin install logstash-output-slack

COPY logstash.conf /usr/share/logstash/pipeline/

CMD ["-f", "/usr/share/logstash/pipeline/logstash.conf"]

logstash.yml:

http.host: "0.0.0.0"
xpack.monitoring.elasticsearch.url: http://elasticsearch:9200
xpack.monitoring.elasticsearch.username: logstash_system
xpack.monitoring.elasticsearch.password: changeme
#xpack.monitoring.enabled: false

Logstash log says Logstash started successfully, there are no any errors logs neither in Logstash nor in ES. Logstash works well but cannot be viewed from Kibana.