Examine source code of OpenCoupon

{
  "manifest_version": 3,
  "name": "OpenCoupon",
  "version": "1.1.0",
  "description": "Open-source community driven coupon finder.",
  "action": {
    "default_popup": "index.html",
    "default_icon": {
      "16": "icon16.png",
      "48": "icon48.png",
      "128": "icon128.png"
    }
  },
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "permissions": [
    "storage",
    "activeTab",
    "tabs"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "opencoupons@addon.local",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}