chromium/chrome/test/data/extensions/api_test/lazy_background_page/browser_action_with_callback/manifest.json

{
  "name": "Extensions Button",
  "description": "Access the Extensions window directly from the toolbar. Will not open a duplicate extensions tab.",
  "version": "1.1",
  "manifest_version": 2,
  "permissions": ["tabs"],
  "background": {
    "scripts": ["background.js"],
    "persistent": false
  },
  "browser_action": {
    "default_icon" : "ext_icon.png",
    "default_title": "Open Extensions window"
  }
}