PropertiesChromeCriOSEdgeFirefoxGooglebotIEOperaSafariSamsungBrowser
length 31.0.1650 62.0.3202 12.0.0 27.0.0 2.1.0?? 3.0.0 6.2.0
prototype 31.0.1650 62.0.3202 12.0.0 27.0.0 2.1.0 9.0.0? 3.0.0 6.2.0
toString 31.0.1650?? 27.0.0 2.1.0?? 4.0.0?