Examine source code of Twitter Flags

{
  "manifest_version": 3,
  "name": "Twitter Flags",
  "version": "1.0.2",
  "description": "Shows the flag of Twitter users next to their username based on their location",
  "permissions": [
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "twitter-flags@jameshahn.me",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "collect_data": false,
        "collect_personal_data": false,
        "collect_usage_data": false
      }
    }
  },
  "web_accessible_resources": [
    {
      "resources": [
        "flags/*.png",
        "pageScript.js"
      ],
      "matches": [
        "https://x.com/*",
        "https://twitter.com/*"
      ]
    }
  ],
  "content_scripts": [
    {
      "matches": [
        "https://x.com/*",
        "https://twitter.com/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "styles.css"
      ],
      "run_at": "document_idle"
    }
  ],
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  }
}