I have followed the angular documentation on service worker and I am able to run the project offline on the local machine. When I try to deploy to Github pages, it's working fine in online mode and I am also able to see files are fetched through service workers in network and service worker is running in application tab but when I try to reload the page in offline mode it's not working.
https://github.com/PrithiviRajG/Angular-Service-Worker is my Github account https://prithivirajg.github.io/Angular-Service-Worker/ is my Github page