Examine source code of Dice Roll

{
  "name": "Dice Roll",
  "version": "1.4",
  "description": "Small extension to roll dice or flip a coin. Choose from a set of default dice or use a custom die.",
  "browser_action": {
    "default_icon": "icons/icon32.png",
    "default_title": "Dice Roll",
    "default_popup": "popup.html"
  },
  "manifest_version": 2,
  "permissions": [
    "storage"
  ],
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "128": "icons/icon128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{22e4c41e-934a-4bae-947e-187356b50b6d}"
    }
  }
}