One of the greatest feature of PWA Extension is adding editable Service Worker File.

This adds a big value if you want to customize service worker for your needs.

Follow steps : 

  1. Go to Plugins
  2. Search for PWA
  3. You will see : System - PWA Progressive Web App
  4. Click on to the title and visit plugin admin panel.
  5. Go to Section / Tab "Extras"
  6. Find parameter "Add custom css" and swith it to "YES"
  7. or Find parameter "Add custom js" and swith it to "YES"
  8. New fields opens automatically : "CustomCSS" and "Custom JS"
  9. Add your code to the text areas
  10. Click to "SAVE" and do this one more time to safe the creation

Now your new custom css or custom js codes will run!!!

You can check it via URL : https://www.your-site-url-here.com/pwaextension-service-worker.js