Safari 10.0 = 0.64%
Safari 8.0 = 0.33%
Safari 9.1 = 0.27%
===================
Total = 3.88%
For July 2017 according to NetMarketshare.
I wouldn't call a 3.88% install base "pretty popular". It's also offers a terrible developer experience
cf: https://www.netmarketshare.com/browser-market-share.aspx?qpr...