Examine source code of Discount Code Manager

{
  "manifest_version": 2,
  "name": "Discount Code Manager",
  "version": "1.0",
  "description": "Store, view, and apply discount codes during online shopping.",
  "permissions": [
    "storage"
  ],
  "browser_action": {
    "default_icon": "icon.png",
    "default_popup": "popup.html",
    "default_title": "Coupon Manager"
  },
  "icons": {
    "48": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{cd1bdfa5-95a9-4268-a102-290ea7f88b79}"
    }
  }
}