PropertiesChromeCriOSEdgeFirefoxGooglebotIEOperaSafariSamsungBrowser
length 15.0.874? 12.0.0 18.0.0 2.1.0?? 3.0.0 6.2.0
prototype 15.0.874? 13.10586.0 55.0.0? 9.0.0? 4.0.0?