Fix for error in Firefox because of workaround for Safari

Fix for #94
RegExp based on user agent examples from http://myip.ms/view/comp_browsers/3458/Safari_8.html beause I do not have any available machine with Safari 8
Simpler fix without regexp checking both getter and setter
Merge pull request #514 from nazar-pc/patch-1

Fix for error in Firefox because of workaround for Safari