This module provides information about your add-on and the environment it's running in.

It also provides messaging APIs enabling you to:

  • Communicate between different parts of your add-on.
  • Communicate with other add-ons.
  • Communicate with native applications.


Represents one end of a connection between two specific contexts, which can be used to exchange messages.

Contains information about the sender of a message or connection request.

Identifies the browser's operating system.
Identifies the browser's processor architecture.
Contains information about the platform the browser is running on.
Result of a call to runtime.requestUpdateCheck().
The reason that the runtime.onInstalled event is being dispatched.
The reason that the runtime.onRestartRequired event is being dispatched.


This value is set when an asynchronous function has an error condition that it needs to report to its caller.
The ID of the add-on.


Retrieves the Window object for the background page running inside the current add-on.

Opens your add-ons's options page.

Gets the complete manifest.json file, serialized as an object.
Given a relative path from the manifest.json to a resource packaged with the add-on, returns a fully-qualified URL.
Sets a URL to be visited when the add-on is uninstalled.
Reloads the add-on.
Checks for updates to this add-on.
Establishes a connection from a content script to the main add-on process, or from one add-on to a different add-on.
Connects the WebExtension to a native application on the user's computer.
Sends a single message to event listeners within your add-on or a different add-on. Similar to runtime.connect but only sends a single message, with an optional response.
Sends a single message from a WebExtension to a native application.
Returns information about the current platform.
Returns a DirectoryEntry for the package directory.


Fired when a profile that has this add-on installed first starts up. This event is not fired when an incognito profile is started.
Fired when the add-on is first installed, when the add-on is updated to a new version, and when the browser is updated to a new version.
Sent to the event page just before the add-on is unloaded. This gives the add-on an opportunity to do some cleanup.
Sent after runtime.onSuspend to indicate that the add-on won't be unloaded after all.
Fired when an update is available, but isn't installed immediately because the add-on is currently running.
Fired when an update for the browser is available, but isn't installed immediately because a browser restart is required.
Fired when a connection is made with either an add-on process or a content script.
Fired when a connection is made with another add-on.
Fired when a message is sent from either an add-on process or a content script.
Fired when a message is sent from another add-on. Cannot be used in a content script.
Fired when the device needs to be restarted.

Browser compatibility

Chrome Edge Firefox Firefox for Android Opera
MessageSender Yes Yes 45.0 48.0 33
OnInstalledReason Yes Yes 45.0 48.0 33
OnRestartRequiredReason Yes No 45.0 48.0 33
PlatformArch Yes No 45.0 48.0 33
PlatformInfo Yes No 45.0 * 48.0 * 33
PlatformNaclArch Yes No 45.0 48.0 33
PlatformOs Yes No 45.0 48.0 33
Port Yes No 45.0 48.0 33
RequestUpdateCheckStatus Yes No No No 33
connect Yes No 45.0 48.0 33
connectNative Yes No 50.0 No 33
getBackgroundPage Yes Yes 45.0 48.0 33
getManifest Yes Yes 45.0 48.0 33
getPackageDirectoryEntry Yes No No No 33
getPlatformInfo Yes No 45.0 48.0 33
getURL Yes Yes 45.0 48.0 33
id Yes Yes 45.0 48.0 33
lastError Yes Yes 47.0 48.0 33
onBrowserUpdateAvailable Yes No No No 33
onConnect Yes No 45.0 48.0 33
onConnectExternal Yes No No No 33
onInstalled Yes Yes No No 33
onMessage Yes Yes * 45.0 48.0 33
onMessageExternal Yes No No No 33
onRestartRequired Yes No No No 33
onStartup Yes No No 48.0 33
onSuspend Yes No No No 33
onSuspendCanceled Yes No No No 33
onUpdateAvailable Yes No No No 33
openOptionsPage Yes No 48.0 No 33
reload Yes No No No 33
requestUpdateCheck Yes No No No 33
sendMessage Yes Yes * 45.0 48.0 33
sendNativeMessage Yes No 50.0 No 33
setUninstallURL Yes No 47.0 48.0 33

Chrome incompatibilities

  • Firefox does not support:
    • getPackageDirectoryEntry()
    • reload()
    • requestUpdateCheck()
    • restart()
    • sendNativeMessage()
    • onBrowserUpdateAvailable
    • onConnectExternal
    • onInstalled
    • onMessageExternal
    • onRestartRequired
    • onStartup
    • onSuspend
    • onSuspendCanceled
    • onUpdateAvailable

Example add-ons


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

Microsoft Edge compatibility data is supplied by Microsoft Corporation and is included here under the Creative Commons Attribution 3.0 United States License.

Document Tags and Contributors

 Contributors to this page: wbamberg, chrisdavidmills
 Last updated by: wbamberg,