Service Worker gotchas – https://medium.com/kollegorna/service-worker-gotchas-af20a9dab986

service-worker-disable-file-cache-nginx

server {
  location ~* (serviceworker\.js)$ {
    add_header 'Cache-Control' 'no-store, no-cache, must-revalidate, proxy-revalidate, max-age=0';
    expires off;
    proxy_no_cache 1;
  }
}

# Or try this block
location /sw.js {
  add_header Cache-Control "no-cache";
  proxy_cache_bypass $http_pragma;
  proxy_cache_revalidate on;
  expires off;
  access_log off;
}