Examine source code of YouTube Language Level

{
  "manifest_version": 3,
  "name": "YouTube Language Level",
  "version": "1.4.12",
  "description": "Analyze YouTube video transcripts to determine CEFR language level (A1-C2) using AI models, via local AI or the Gemini API",
  "permissions": [
    "storage",
    "declarativeNetRequestWithHostAccess"
  ],
  "host_permissions": [
    "https://www.youtube.com/*",
    "https://yt-transcript-proxy.fz4mbelli.workers.dev/*",
    "https://youtube-transcript.ai/*",
    "https://kome.ai/*",
    "https://generativelanguage.googleapis.com/*",
    "http://localhost/*",
    "http://127.0.0.1/*"
  ],
  "optional_host_permissions": [
    "http://*/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "eggprise1@gmail.com",
      "strict_min_version": "128.0",
      "data_collection_permissions": {
        "required": [
          "websiteContent"
        ]
      }
    }
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.youtube.com/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "styles.css"
      ]
    }
  ],
  "background": {
    "service_worker": "background.js",
    "scripts": [
      "transcript-sources.js",
      "background.js"
    ]
  },
  "action": {
    "default_popup": "popup.html",
    "default_title": "YT Level"
  },
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  }
}