page_action

Type Object
Mandatory No
Manifest version 2 or higher
Example
json

"page_action": {
  "default_icon": {
    "19": "button/geo-19.png",
    "38": "button/geo-38.png"
  },
  "default_title": "Whereami?",
  "default_popup": "popup/geo.html"
}

A page action is an icon that your extension adds inside the browser's URL bar.

Your extension may optionally also supply an associated popup whose content is specified using HTML, CSS, and JavaScript.

You must specify this key to include a page action in your extension. When specified, you can manipulate the button programmatically using the pageAction API.

If you supply a popup, then the popup is opened when the user clicks the icon, and your JavaScript running in the popup can handle the user's interaction with it. If you don't supply a popup, then a click event is dispatched to your extension's background scripts when the user clicks the icon.

Page actions are like browser actions, except that they are associated with particular web pages rather than with the browser as a whole. If an action is only relevant on certain pages, then you should use a page action and display it only on relevant pages. If an action is relevant to all pages or to the browser itself, use a browser action.

While browser actions are displayed by default, page actions are hidden by default. They can be shown for a particular tab by calling pageAction.show(), passing in the tab's id. You can also change this default behavior using the show_matches property.

Syntax

The page_action key is an object that may have any of three properties, all optional:

Name Type Description
browser_style
Optional
in Manifest V3. 		Boolean

Optional. Defaults to false.

Do not set browser_style to true: its not support in Manifest V3 from Firefox 118. See Manifest V3 migration for browser_style.

In Firefox, the stylesheet can be seen at chrome://browser/content/extension.css or chrome://browser/content/extension-mac.css on macOS.

The latest-download example extension uses browser_style in its popup.

default_icon Object or String

Use this to specify an icon for the action.

It's recommended that you supply two icons here (19×19 pixels and 38×38 pixels), and specify them in an object with properties named "19" and "38", like this:

json

    "default_icon": {
      "19": "geo-19.png",
      "38": "geo-38.png"
    }

If you do this, then the browser will pick the right size icon for the screen's pixel density.

You can just supply a string here:

json
"default_icon": "geo.png"

If you do this, then the icon will be scaled to fit the toolbar, and may appear blurry.

default_popup String

The path to an HTML file containing the specification of the popup.

The HTML file may include CSS and JavaScript files using <link> and <script> elements, just like a normal web page. However, don't use <script> with embedded code, because you'll get a Content Violation Policy error. Instead, <script> must use the src attribute to load a separate script file.

Unlike a normal web page, JavaScript running in the popup can access all the WebExtension APIs (subject, of course, to the extension having the appropriate permissions).

This is a localizable property.

default_title String

Tooltip for the icon, displayed when the user moves their mouse over it.

This is a localizable property.

hide_matches Array of Match Pattern except <all_urls>

Hide the page action by default for pages whose URLs match any of the given match patterns.

Note that page actions are always hidden by default unless show_matches is given. Therefore, it only makes sense to include this property if show_matches is also given, and will override the patterns in show_matches.

For example, consider a value like:

json

"page_action": {
  "show_matches": ["https://*.mozilla.org/*"],
  "hide_matches": ["https://developer.mozilla.org/*"]
}

This shows the page action by default for all HTTPS URLs under the "mozilla.org" domain, except for pages under "developer.mozilla.org".

show_matches Array of Match Pattern

Show the page action by default for pages whose URLs match any of the given patterns.

See also hide_matches.
pinned Boolean

Optional. Defaults to true.

Controls whether or not the page action should appear in the location bar by default when the user installs the extension. This property is no longer supported since Firefox 89.

Example

json
"page_action": {
  "default_icon": {
    "19": "button/geo-19.png",
    "38": "button/geo-38.png"
  }
}

A page action with just an icon, specified in 2 different sizes. The extension's background scripts can receive click events when the user clicks the icon using code like this:

js
browser.pageAction.onClicked.addListener(handleClick);
json
"page_action": {
  "default_icon": {
    "19": "button/geo-19.png",
    "38": "button/geo-38.png"
  },
  "default_title": "Whereami?",
  "default_popup": "popup/geo.html"
}

A page action with an icon, a title, and a popup. The popup will be shown when the user clicks the icon.

Browser compatibility

BCD tables only load in the browser

See also