Browser Feature Detection
if('querySelector' in document
&& 'localStorage' in window
&& 'addEventListener' in window) {
// Modern browser. Let's add JavaScript functionality
}
/*
With this in place, we have two groups of browsers,
modern (IE9+, Fx, Safari, Opera, Chrome, iOS, Android 2.1+, …)
and old (IE8-, Blackberry, …).
*/
// detection extended with support for ServiceWorker availability
if ('visibilityState' in document) {
// Modern browser. Let's load JavaScript
if ('serviceWorker' in navigator) {
// Let's add offline support
navigator.serviceWorker.register('sw.js', {
scope: './'
});
}
}