Used to check https://github.com/SeleniumHQ/docker-selenium/issues/447

docker-compose-base.yml

version: '2.1'

services:
  app:
    extends:
      file: ../../docker-compose.yml
      service: app
    environment:
      # Path is relative to the location of the dev server.
      - WEBPACK_CONFIG=./acceptance/webpack.config.acceptance.js
    expose:
      - '3000'
    volumes:
      - ./screenshots:/usr/src/app/tests/acceptance/screenshots

  selenium:
    image: selenium/hub
    expose:
      - '4444'
    ports:
      - '4444:4444' # so we can ping for the status of the nodes
    environment:
      - GRID_DEBUG=true
    devices:
      # Try to prevent Selenium from blocking when creating sessions due to
      # limitd entropy.
      - /dev/urandom:/dev/random

  chrome:
    image: selenium/node-chrome

  firefox:
    image: selenium/node-firefox