Trying to run testcafe trough gitlab CI

I am trying to run my end to end tests (using testcafe) during the CI pipeline of gitlab. However I am running into the following error:

ERROR The Firefox 52.0.0 / Linux 0.0.0 browser disconnected. This problem may appear when a browser hangs or is closed, or due to network issues.

My .gitlab-ci.yml is as follows:

  - test

    - ##Some git specific stuff...
    - apt-get update -yqqq
    - apt-get install -y xvfb
    - apt-get install iceweasel -yqq
    - Xvfb :99 -ac &
    - export DISPLAY=:99

  image: node:7.7.4
  stage: test
    - npm install
    - npm install -g testcafe@0.19.2
    - testcafe --list-browsers
    - testcafe firefox e2etests/tests/login.test.js
    - vue

So basically I am using a node docker image for my test ‘stage’ and install xvfb to ‘display’ a browser.