tabs.connect()

Call this function to set up a connection between the extension's background scripts (or other privileged scripts, such as popup scripts or options page scripts) and any content scripts that belong to this extension and are running in the specified tab. This function returns aruntime.Port object.

When this is called, theruntime.onConnect event will be fired in any content script belonging to this extension that are running in the specified tab. The event listener will be passed anotherruntime.Port object. The two sides can then use thePort objects to exchange messages.

For more details, seeconnection-based messaging. You can message without creating a connection, for advice on choosing between the options, seeChoosing between one-off messages and connection-based messaging.

Syntax

browser.tabs.connect(  tabId,      // integer  connectInfo // optional object)

Parameters

tabId

integer. ID of the tab whose content scripts we want to connect to.

connectInfoOptional

An object with the following properties:

nameOptional: string. Will be passed intoruntime.onConnect event listeners in content scripts belonging to this extension and running in the specified tab.
frameIdOptional: integer. Open a port to a specific frame identified byframeId instead of all frames in the tab.

Return value

runtime.Port. A port that can be used to communicate with the content scripts running in the specified tab.

Examples

In this example a background script listens for a click on abrowser action, then connects to the currently active tab, then sends a message using thePort that's returned fromconnect():

function connectToTab(tabs) {  if (tabs.length > 0) {    let examplePort = browser.tabs.connect(tabs[0].id, {      name: "tabs-connect-example",    });    examplePort.postMessage({ greeting: "Hi from background script" });  }}function onError(error) {  console.log(`Error: ${error}`);}browser.browserAction.onClicked.addListener(() => {  let gettingActive = browser.tabs.query({    currentWindow: true,    active: true,  });  gettingActive.then(connectToTab, onError);});