Examine source code of Decline Amazon Prime

{
  "manifest_version": 3,
  "name": "Decline Amazon Prime",
  "version": "1.1",
  "description": "Declines Amazon Prime offer during checkout",
  "permissions": [
    "tabs"
  ],
  "host_permissions": [
    "*://*.amazon.com/*",
    "*://*.amazon.ca/*",
    "*://*.amazon.co.uk/*",
    "*://*.amazon.de/*",
    "*://*.amazon.fr/*",
    "*://*.amazon.es/*",
    "*://*.amazon.it/*",
    "*://*.amazon.nl/*",
    "*://*.amazon.se/*",
    "*://*.amazon.pl/*",
    "*://*.amazon.be/*",
    "*://*.amazon.com.au/*",
    "*://*.amazon.co.jp/*",
    "*://*.amazon.cn/*",
    "*://*.amazon.in/*",
    "*://*.amazon.com.br/*",
    "*://*.amazon.com.mx/*",
    "*://*.amazon.ae/*",
    "*://*.amazon.sg/*",
    "*://*.amazon.com.tr/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "decline-prime-offer@Tortugu22",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  }
}