Examine source code of CheckOut.Champ

{
  "manifest_version": 2,
  "name": "CheckOut.Champ",
  "version": "1.5",
  "description": "Shop online, get points for your purchases and redeem them to get gift cards!",
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "background": {
    "scripts": [
      "browser-polyfill.js",
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.amazon.com/*"
      ],
      "js": [
        "browser-polyfill.js",
        "content.js"
      ]
    }
  ],
  "icons": {
    "48": "icon.png",
    "96": "icon.png"
  },
  "permissions": [
    "storage",
    "webNavigation",
    "*://*.amazon.com/*",
    "*://*.onrender.com/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{de367e46-971c-4ebd-869f-75e1e267c7c9}",
      "strict_min_version": "58.0"
    }
  }
}