Firefox is dead, it's at 6% market share now:
Chrome 57.36% 60.60% 47.77%
Safari 13.96% 17.27% 22.16%
UC 7.88% 1.69% 0.32%
Firefox 5.45% 5.89% 6.21%
https://en.wikipedia.org/wiki/Usage_share_of_web_browsers