https://docs.travis-ci.com/user/gui-and-headless-browsers/#using-xvfb-to-run-tests-that-require-a-gui
https://docs.travis-ci.com/user/gui-and-headless-browsers/#using-xvfb-to-run-tests-that-require-a-gui

caktus/django-scribbler,caktus/django-scribbler,caktus/django-scribbler,caktus/django-scribbler