Demonstrates access keys in the menus API.

This add-on uses the menus namespace to access the functions it needs to create menu items. Note that Chrome, Edge, and Opera all use the contextMenus namespace for this, so this extension will not work in these browsers. For compatibility with these browsers, Firefox also offers the contextMenus namespace, so to make this extension work with other browsers, use contextMenus.

This extension adds a menu item that has an access key. An access key allows users to activate the menu item with one keystroke. On Linux and Windows, the chosen access key is underlined. On macOS, access keys are supported too, but without visual indicators.

When an access key is shared by multiple menu items, pressing the key will switch between the menu items that share the access key. Otherwise (if an access key is bound to one menu item only), the menu item is clicked.

The menu item in this demo logs a message to the extension's console upon click. This console can be shown via the "Debug" button at about:debugging .

• Specifying access keys via & in the menu item title.
• Detecting feature support, exemplified by detecting support for the visible property of the menus.update API that was also introduced in Firefox 63.

As access keys are only supported in Firefox 63 and later, this example also shows how one can detect the feature support in the browser and fall back to menu items without access keys if needed.