Is ServiceWorker intended to replace Appcache, or is the intention that the two will coexist? Phrased another way, is appcache about to become deprecated?
Blink's Service Worker team is keen on deprecating AppCache (We will follow our usual intent to deprecate process). We believe that Service Worker is a much better solution. Also, it should be pretty easy to offer a drop-in replacement for AppCache built on top of SW. We'll start by collecting usage metrics and do some outreach.
AppCache and Service Worker should coexist without any issue since offering offline support via AppCache for browsers that don't support Service Workers is a valid use case. @flo850 If it's not working, please let us know by filing a bug.