runtime.MessageSender

An object containing information about the sender of a message or connection request; this is passed to the runtime.onMessage() listener.

It is also a property of runtime.Port, but only in the Port instance passed into the runtime.onConnect() or runtime.onConnectExternal() listeners.

Type

Values of this type are objects. They contain the following properties:

tabOptional

tabs.Tab. The tabs.Tab which opened the connection. This property will only be present when the connection was opened from a tab (including content scripts).

frameIdOptional

integer. The frame that opened the connection. Zero for top-level frames, positive for child frames. This will only be set when tab is set.

idOptional

string. The ID of the extension that sent the message, if the message was sent by an extension. If the sender set an ID explicitly using the applications key in manifest.json, then id will have this value. Otherwise it will have the ID that was generated for the sender.

Note that in Firefox, before version 54, this value was the extension's internal ID (that is, the UUID that appears in the extension's URL).

urlOptional

string. The URL of the page or frame hosting the script that sent the message.

If the sender is a script running in an extension page (such as a background page, an options page, or a browser action or page action popup), the URL will be in the form "moz-extension://<extension-internal-id>/path/to/page.html". If the sender is a background script and you haven't included a background page, it will be "moz-extension://<extension-internal-id>/_generated_background_page.html".

If the sender is a script running in a web page (including content scripts as well as normal page scripts), then url will be the web page URL. If the script is running in an iframe, url will be the iframe's URL.

tlsChannelIdOptional

string. The TLS channel ID of the page or frame that opened the connection, if requested by the extension, and if available.

Browser compatibility