pwa beispiel als Grundlage
wetter pwa Beispiel
selfhtml XMLHttpRequest
w3schools js_json_http
selfhtml fetch
developer.mozilla Fetch_API
robisys.de
service-worker
https://developers.google.com/web/updates/2015/03/introduction-to-fetch https://query.yahooapis.com/v1/public/yql https://jakearchibald.com/2014/offline-cookbook/#cache-then-network https://jakearchibald.com/2014/offline-cookbook/#cache-falling-back-to-network https://developer.mozilla.org/de/docs/Web/API/Fetch_API
jakearchibald offline-cookbook
robisys.de app.js