Examine source code of Simple Notepad

{
  "manifest_version": 2,
  "name": "Simple Notepad",
  "version": "1.0.3",
  "description": "A lightweight, no-frills notepad for Firefox.",
  "browser_action": {
    "default_icon": {
      "48": "icons/pad_48.png"
    },
    "default_title": "Notepad",
    "default_popup": "notepad.html"
  },
  "options_ui": {
    "page": "options.html"
  },
  "permissions": [
    "storage"
  ],
  "icons": {
    "48": "icons/pad_48.png",
    "128": "icons/pad_128.png"
  },
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Ctrl+Shift+F"
      },
      "description": "Opens the notepad"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "poolreedloopdeer@gmail.com"
    }
  }
}