title: Implementing Service Workers with an appcache fallback for unsupported browsers
body: <p>I'm looking into techniques for building a Progressive Web App in Aurelia with offline functionality that works across the major browsers. Service Workers are seemingly the preferred option for asset caching, but with lack of support in Safari (and currently Edge). Is it possible to use service workers with a fallback to appcache if they're not supported? How will an application behave if there's an appcache manifest AND a service worker installed?</p>