Examine source code of Quick Notepad

{
  "manifest_version": 2,
  "name": "Quick Notepad",
  "version": "1.0",
  "description": "A simple notepad for your browser to quickly jot down ideas or tasks.",
  "permissions": [
    "storage"
  ],
  "browser_action": {
    "default_icon": "icons/notepad-48.png",
    "default_popup": "popup.html",
    "default_title": "Quick Notepad"
  },
  "icons": {
    "48": "icons/notepad-48.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{2ff8f799-2c26-4d62-8c31-2147daa4b054}"
    }
  }
}