Examine source code of Bookmark Manager

{
  "manifest_version": 2,
  "name": "Bookmark Manager",
  "version": "3.0",
  "permissions": [
    "storage",
    "activeTab",
    "tabs"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_title": "Bookmark Manager"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "bookmark-manager@example.com"
    }
  }
}