diff --git a/.travis.yml b/.travis.yml
index 7547739aeb55..a6ac4d55abfc 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -12,6 +12,8 @@ addons:
 before_install:
   - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.30.1/install.sh | bash; fi
   - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then source ~/.nvm/nvm-exec; fi
+  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then brew update; fi
+  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then brew install Caskroom/cask/firefox; fi
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then export DISPLAY=:99.0; fi
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sh -e /etc/init.d/xvfb start; fi
   - nvm install $NODE_VERSION