Examine source code of Gmail Walculizer

{
  "manifest_version": 3,
  "name": "Gmail Walculizer",
  "description": "Modifica los elementos de Gmail según tus necesidades",
  "version": "1.0",
  "content_scripts": [
    {
      "js": [
        "scripts/content.js"
      ],
      "css": [
        "content/walcu.styles.css"
      ],
      "matches": [
        "https://mail.google.com/mail/*"
      ]
    }
  ],
  "action": {
    "default_popup": "popup/popup.html"
  },
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{4de1cfcb-f4b6-4510-a4ad-709a430691c7}",
      "strict_min_version": "109.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "permissions": [
    "storage"
  ]
}