Examine source code of Ad Ninja

{
  "manifest_version": 2,
  "name": "Ad Ninja",
  "version": "1.0",
  "description": "Detect ad-like elements and turn them into a playful tap-to-smash mini-game (does not block content).",
  "permissions": [
    "activeTab",
    "storage"
  ],
  "browser_action": {
    "default_title": "Ad Ninja",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content-script.js"
      ],
      "css": [
        "adninja.css"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "adninja@example.com",
      "strict_min_version": "60.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}