title: Multiple instances of self.__WB_MANIFEST
body: <p>(Related to <a href="https://forum.quasar-framework.org/topic/7808/injectmanifest-precaching-not-working" rel="nofollow noreferrer">this question</a>)</p>
  <p>I am using quasar v2.0.0-beta.5 and &quot;workbox-webpack-plugin&quot;: &quot;^5.1.4&quot;, following a pwa tutorial. I am now working on the service workers part using workboxPluginMode: 'InjectManifest' in quasar.conf.js. My custom-service-worker.js is just:</p>
  <pre><code>import { precacheAndRoute } from 'workbox-precaching'
  precacheAndRoute(self.__WB_MANIFEST)
  </code></pre>
  <p>I get the following error when loading the pwa</p>
  <blockquote>
  <p>Uncaught not-an-array: The parameter 'entries' passed into
  'workbox-precaching.PrecacheController.addToCacheList()' must be an
  array</p>
  </blockquote>
  <p>I have updated to lastest version of Workbox: <code>npm install --save-dev workbox-webpack-plugin@^6.1.0</code> to see if it makes a difference and now I get the following error during the <code>quasar dev -m pwa</code></p>
  <blockquote>
  <p>Multiple instances of self.__WB_MANIFEST were found in your SW source.
  Include it only once. For more info, see GoogleChrome/workbox#2681</p>
  </blockquote>
  <p>The problem is that without fixing this problem, I am not able to debug the different cache strategies.</p>
  <blockquote>
  <p>Platform (please complete the following information): Quasar Version:
  v2.0.0-beta.5 @quasar/app Version: v3.0.0-beta.7 Quasar mode: [ ] SPA
  [ ] SSR [x ] PWA [ ] Electron [ ] Cordova [ ] Capacitor [ ] BEX Tested
  on: [ ] SPA [ ] SSR [x ] PWA [ ] Electron [ ] Cordova [ ] Capacitor [
  ] BEX OS: windows 10 Node: v14.15.1 NPM: 6.14.8 Yarn: 1.22.10
  Browsers: chrome (latest) iOS: Android: Electron:</p>
  </blockquote>