BrowserVersionOwn?TypeAs String
Chrome81.0.4044???
Edge86.0.622???
Firefox68.0.0???
HeadlessChrome81.0.4044???
IE10.0.0???
Safari10.1.2???
Safari13.0.4ownfunctionfunction ScreenLuminance() { [native code] }
Safari14.0.0???

PropertiesChromeEdgeFirefoxHeadlessChromeIESafari
length????? 13.0.4
prototype????? 13.0.4