Examine source code of FC Enhancer

{
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "js": [
        "contentscript.js"
      ],
      "matches": [
        "https://www.ea.com/ea-sports-fc/ultimate-team/web-app/*",
        "https://www.ea.com/*/ea-sports-fc/ultimate-team/web-app/*"
      ]
    }
  ],
  "description": "Enhances your experience with FIFA web app",
  "host_permissions": [
    "https://www.ea.com/*",
    "https://futbin.com/*",
    "https://www.futbin.com/*",
    "https://futbin.org/*",
    "https://*.lambda-url.eu-west-1.on.aws/*",
    "https://exp.host/*",
    "https://futnext.com/",
    "https://*.futnext.com/",
    "https://*.futnext.com/*"
  ],
  "icons": {
    "16": "icon16.png",
    "32": "icon32.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "key": "MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAiwngzEmkJb5MF6jKtOy1UAzHw8E8kuvJ5VaNX2KG76vfXZl2qywynbqLsTkpJBeE8HLNH9wLgV8gHf3BsNXgbNiU9Pisbl5C/2s09By2Cqc4OijUJ+dmlm96Quc/Aoh8ysZrYKX/DJKK6m7S/x7/CtCnqBHUtGlpoSyw3xATbXHsF8m8xw+VlUMO3l/OU/rX6CBy5TLZROdb1CEg71BdPRVXBXCnIeBtPM79DGu9lZ5aXWGfnDpPf2nggcgntRkHa4fyEEJCmjcFqeV9O9lQB2OBblbMychmvza6TrKjrhphKyOD3cWxKXYuxuTbDQnWSASCB3pPuJhVRCL8T2Fq7wIDAQAB",
  "manifest_version": 3,
  "name": "FC Enhancer",
  "permissions": [
    "notifications"
  ],
  "update_url": "https://clients2.google.com/service/update2/crx",
  "version": "1.0.9.2",
  "web_accessible_resources": [
    {
      "matches": [
        "<all_urls>"
      ],
      "resources": [
        "js/vendor.js",
        "js/main.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "fcEnhancer1@xyz.com",
      "strict_min_version": "57.0"
    }
  }
}