index.md

---

title: runtime.onBrowserUpdateAvailable
slug: Mozilla/Add-ons/WebExtensions/API/runtime/onBrowserUpdateAvailable
page-type: webextension-api-event
tags:
  - API
  - Add-ons
  - Deprecated
  - Event
  - Extensions
  - Non-standard
  - Reference
  - WebExtensions
  - onBrowserUpdateAvailable
  - runtime
browser-compat: webextensions.api.runtime.onBrowserUpdateAvailable

---

{{AddonSidebar}}{{Deprecated_header}}

Fired when an update for the browser is available, but it isn't installed immediately because a browser restart is required.

Syntax

browser.runtime.onBrowserUpdateAvailable.addListener(listener)
browser.runtime.onBrowserUpdateAvailable.removeListener(listener)
browser.runtime.onBrowserUpdateAvailable.hasListener(listener)

Events have three functions:

• addListener(callback)

  • : Adds a listener to this event.

• removeListener(listener)

  • : Stop listening to this event. The listener argument is the listener to remove.

• hasListener(listener)

  • : Checks whether a listener is registered for this event. Returns true if it is listening, false otherwise.

addListener syntax

Parameters

• function

  • : A callback function that will be called when this event occurs.

Browser compatibility

{{Compat}}

Examples

Listen for this event:

function handleBrowserUpdateAvailable() {
  // handle event
}

browser.runtime.onBrowserUpdateAvailable.addListener(handleBrowserUpdateAvailable);

{{WebExtExamples}}

Note: This API is based on Chromium's chrome.runtime API. This documentation is derived from runtime.json in the Chromium code.