selenium docker fail

Dockerfile

FROM selenium/standalone-firefox
USER root

# screenshot default port is 3000
EXPOSE 3000

# netcat is used by scripts/ci-tests to check if the server is up
# vim is installed cuz lulz
RUN apt-get update && apt-get install -y \
  curl \
  imagemagick \
  make \
  g++ \
  xz-utils \
  git \
  python-pip \
  netcat

# install node 6.9.5
RUN set -ex \
  && for key in \
    9554F04D7259F04124DE6B476D5A82AC7E37093B \
    94AE36675C464D64BAFA68DD7434390BDBE9B9C5 \
    0034A06D9D9B0064CE8ADF6BF1747F4AD2306D93 \
    FD3A5288F042B6850C66B31F09FE44734EB7990E \
    71DCFD284A79C3B38668286BC97EC7A07EDE3FC1 \
    DD8F2338BAE7501E3DD5AC78C273792F7D83545D \
    B9AE9905FFD7803F25714661B63B535A4C206CA9 \
    C4F0DFFF4E8C1A8236409D08E73BC641CC11F4C8 \
    56730D5401028683275BD23C23EFEFE93C4CFFFE \
  ; do \
    gpg --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys "$key"; \
  done

ENV NPM_CONFIG_LOGLEVEL info
ENV NODE_VERSION 6.9.5

RUN curl -SLO "https://nodejs.org/dist/v$NODE_VERSION/node-v$NODE_VERSION-linux-x64.tar.xz" \
  && curl -SLO "https://nodejs.org/dist/v$NODE_VERSION/SHASUMS256.txt.asc" \
  && gpg --batch --decrypt --output SHASUMS256.txt SHASUMS256.txt.asc \
  && grep " node-v$NODE_VERSION-linux-x64.tar.xz\$" SHASUMS256.txt | sha256sum -c - \
  && tar -xJf "node-v$NODE_VERSION-linux-x64.tar.xz" -C /usr/local --strip-components=1 \
  && rm "node-v$NODE_VERSION-linux-x64.tar.xz" SHASUMS256.txt.asc SHASUMS256.txt \
  && ln -s /usr/local/bin/node /usr/local/bin/nodejs

WORKDIR /usr/src
RUN npm install selenium-webdriver
CMD xvfb-run --server-args='-screen 0, 2560x1440x24' node ./node_modules/selenium-webdriver/example/google_search.js