Add contextmenu items to a Chrome extension’s browser action button

It is now possible, AdBlock chrome extensions has it. Below is working example of “context menu in browser action”.

manifest.json:

{
    "name": "Custom context menu in browser action",
    "version": "1",
    "manifest_version": 2,
    "background": {
      "scripts": ["background.js"]
    },
    "browser_action": {
      "default_title": "Some tooltip",
      "default_popup": "popup.html"
    },
    "permissions": [
      "contextMenus"
    ],
    "icons": {
      "16": "icon16.png"
    }
}

background.js:

chrome.contextMenus.removeAll();
chrome.contextMenus.create({
      title: "first",
      contexts: ["browser_action"],
      onclick: function() {
        alert('first');
      }
});

Note that if you use an Event page, you cannot use the onclick attribute; you’ll need to add a listener to chrome.contextMenus.onClicked instead.