self.addEventListener('install', e => { self.skipWaiting() })
self.addEventListener('activate', e => { e.waitUntil(clients.claim()) })
self.addEventListener('fetch', e => {
  e.respondWith(
    caches.match(e.request).then(r => r || fetch(e.request).then(res => {
      const clone = res.clone()
      caches.open('galikon-v1').then(c => c.put(e.request, clone))
      return res
    }).catch(() => caches.match(e.request)))
  )
})