We're unable to support Safari for Windows due to its age, it no longer being maintained by Apple, and it not making use of modern web standards. It isn't particularly clear but Safari for Windows is still at version 5.1 which is from 2012 and there hasn't been any feature updates to it since then. Web has moved on!
As a side note, Internet Explorer 11 is the oldest browser we support (2013), but given that it will soon be superseded by "original" Microsoft Edge and further superseded by "Chromium" Microsoft Edge I wouldn't expect IE11 to be supported in XF 2.2 either.