Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
Note: This feature is only available in Service Workers.
The registration read-only property of the BackgroundFetchEvent interface returns a BackgroundFetchRegistration object.
A BackgroundFetchRegistration.
In this example, if the user clicks on the user interface displaying the download progress, this fires the backgroundfetchclick event. The current BackgroundFetchRegistration is returned by calling event.registration.
addEventListener("backgroundfetchclick", (event) => {
console.log(event.registration);
});