Examine source code of Walmart Extractor de Precios

{
  "manifest_version": 3,
  "name": "Walmart Extractor de Precios",
  "version": "1.0",
  "description": "Extrae los precios finales de los productos en el checkout de Walmart México.",
  "permissions": [
    "activeTab",
    "scripting"
  ],
  "host_permissions": [
    "https://www.walmart.com.mx/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "action": {
    "default_title": "Mostrar/Ocultar extractor de precios",
    "default_icon": {
      "48": "iconos/icono-48.png"
    }
  },
  "icons": {
    "48": "iconos/icono-48.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "walmart-extractor@local.extension",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.walmart.com.mx/checkout/review-order*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "styles.css"
      ]
    }
  ]
}