This extension will deny automatic registration of service workers. Service workers who have already registered before the extension was introduced will be unregistered when they visit your site for the first time after the extension was introduced. If you want to allow service workers to register on some of your sites, you can add the domain name to the whitelist so that the service workers will not be denied registration.
If your extension is not reject Service Worker, check the following settings in Firefox
about:config
extensions.serviceWorkerRegister.allowed = true
If the above is not set, the extension will not be able to access the Service Worker on the page, and the extension will not work as intended.
