Examine source code of Notes Manager

{
  "manifest_version": 2,
  "name": "Notes Manager",
  "version": "1.0",
  "description": "Manage and organize your notes.",
  "permissions": [
    "storage"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "48": "icons/icon.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{4fa40a46-9a0a-460e-93b3-95e410559986}"
    }
  }
}