BackgroundFetchUpdateUIEvent: updateUI() method

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

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 updateUI() method of the BackgroundFetchUpdateUIEvent interface updates the title and icon in the user interface to show the status of a background fetch.

This method may only be run once, to notify the user on a failed or a successful fetch.




options Optional

An object containing any of the following:

icons Optional

A list of one or more image resources, containing icons for use in the user interface. An image resource is an object containing:


A string which is a URL of an image.

sizes Optional

A string which is equivalent to the sizes attribute of the <link> element.

type Optional

A string containing an image MIME type.

label Optional

A string providing a name for the associated image.

title Optional

A string containing the new title of the user interface.

Return value


InvalidStateError DOMException

Thrown if any of the following are true:


The following example demonstrates updating the UI with a title and image icon on a successful fetch.

addEventListener("backgroundfetchsuccess", (event) => {
    title: "Episode 5 ready to listen!",
    icon: {
      src: "path/to/success.ico",
      sizes: "16x16 32x32 64x64",


Background Fetch
# background-fetch-update-ui-event-update-ui

Browser compatibility

BCD tables only load in the browser