self.addEventListener("install", function(event) { event.waitUntil(caches.open("cache").then(function(cache) { var synth = new Response('', {headers:{"Content-Type": "text/html"}}); return Promise.all([ cache.add("index.html"), cache.put("synth-sw.html", synth), ]); })); }); self.addEventListener("fetch", function(event) { if (event.request.url.indexOf("index.html") >= 0) { event.respondWith(caches.match(event.request)); } else if (event.request.url.indexOf("synth-sw.html") >= 0) { event.respondWith(caches.match(event.request)); } else if (event.request.url.indexOf("synth-window.html") >= 0) { event.respondWith(caches.match(event.request)); } else if (event.request.url.indexOf("synth.html") >= 0) { event.respondWith(new Response('', {headers:{"Content-Type": "text/html"}})); } });