Examine source code of bro3_remove_banner

{
  "manifest_version": 3,
  "name": "bro3_remove_banner",
  "version": "2025.12.4",
  "description": "ブラウザ三国志のプレイ画面からバナー広告を除去する",
  "browser_specific_settings": {
    "gecko": {
      "id": "bro3_remove_banner@addons.mozilla.org",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "host_permissions": [
    "*://*.3gokushi.jp/*"
  ],
  "permissions": [
    "declarativeNetRequest",
    "storage"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*.3gokushi.jp/*"
      ],
      "js": [
        "content-script.js"
      ],
      "css": [
        "content.css"
      ]
    }
  ],
  "background": {
    "scripts": [
      "service-worker.js"
    ],
    "service_worker": "service-worker.js",
    "type": "module"
  },
  "options_ui": {
    "page": "options.html"
  },
  "declarative_net_request": {
    "rule_resources": [
      {
        "id": "bro3_remove_banner",
        "enabled": true,
        "path": "rules.json"
      }
    ]
  }
}