No matching service worker detected. code example

Example: no matching service worker issue

#### For wordpress 

Cache is usually the cause. Empty the cache completely. If you have a cache 
plugin – clear that and the minify js too. If you use a CDN like Cloudflare – 
clear the cache there. If you have installed the site as a web-app, then 
uninstall and make sure u check “Clear data” prompt on uninstall.

Clash of plugins – do you have 2 PWA plugins? Do the old disable 1 plugin at a 
time and retry.

Also, the popup may only show on scroll up or down.


#### For other techs

Place the service worker script file at the root of your website and set 
start_url to /, or place it wherever you want and use the scope property and 
the Service-Worker-Allowed HTTP header as in my other answer.