BrowserVersionOwn?TypeAs String
Chrome86.0.4240ownfunctionfunction PushSubscriptionOptions() { [native code] }
Chrome88.0.4291???
Chrome88.0.4292ownfunctionfunction PushSubscriptionOptions() { [native code] }
Edge86.0.622ownfunctionfunction PushSubscriptionOptions() { [native code] }
Edge87.0.651???
Edge87.0.658ownfunctionfunction PushSubscriptionOptions() { [native code] }
Firefox78.0.0???
Firefox79.0.0ownfunctionfunction PushSubscriptionOptions() { [native code] }
IE7.0.0???
Safari10.1.2???

PropertiesChromeEdgeFirefoxIESafari
length 86.0.4240 86.0.622 79.0.0??
prototype 86.0.4240 86.0.622 79.0.0??