replace old service-worker file with a new one that unregister all of them

static/service-worker.js

@@ -0,0 +1,21 @@
+"use strict";
+
+if ('serviceWorker' in navigator) {
+  navigator.serviceWorker.getRegistrations().then(function (registrations) {
+    if (!registrations.length) {
+      console.log('No serviceWorker registrations found.')
+      return
+    }
+    for (let registration of registrations) {
+      registration.unregister().then(function (boolean) {
+        console.log(
+          (boolean ? 'Successfully unregistered' : 'Failed to unregister'), 'ServiceWorkerRegistration\n' +
+          (registration.installing ? '  .installing.scriptURL = ' + registration.installing.scriptURL + '\n' : '') +
+          (registration.waiting ? '  .waiting.scriptURL = ' + registration.waiting.scriptURL + '\n' : '') +
+          (registration.active ? '  .active.scriptURL = ' + registration.active.scriptURL + '\n' : '') +
+          '  .scope: ' + registration.scope + '\n'
+        )
+      })
+    }
+  });
+}