3 ms·Mac OS X 27. 10.27? But that means there were two each of 10.11, 10.12, 10.13, 10.14, and 10.15 :-)by zapzupnz 3mo agoMac OS X 27. 10.27? But that means there were two each of 10.11, 10.12, 10.13, 10.14, and 10.15 :-)