Examine source code of Block Gmail Ads

{
  "manifest_version": 2,
  "name": "Block Gmail Ads",
  "version": "1.0.0",
  "description": "Bloquea los anuncios de Gmail.",
  "icons": {
    "48": "icon.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://mail.google.com/*"
      ],
      "css": [
        "style.css"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{74280c54-e076-4656-b2ac-2839eb86e68f}"
    }
  }
}