Examine source code of Return YouTube Summary

{
  "manifest_version": 2,
  "name": "Return YouTube Summary",
  "version": "0.5.6",
  "description": "One-click AI summaries of YouTube videos through your own LLM API key. No backend, no tracking.",
  "browser_specific_settings": {
    "gecko": {
      "id": "return-youtube-summary@nalg.dev",
      "strict_min_version": "115.0",
      "data_collection_permissions": {
        "required": [
          "websiteContent",
          "authenticationInfo"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  },
  "permissions": [
    "storage",
    "webRequest",
    "webRequestBlocking",
    "https://www.youtube.com/*",
    "https://m.youtube.com/*"
  ],
  "optional_permissions": [
    "https://api.openai.com/*",
    "https://api.anthropic.com/*",
    "https://api.z.ai/*",
    "https://generativelanguage.googleapis.com/*",
    "https://openrouter.ai/*",
    "https://api.groq.com/*",
    "http://localhost/*",
    "http://127.0.0.1/*",
    "https://*/*"
  ],
  "background": {
    "scripts": [
      "background/background.js"
    ],
    "persistent": true
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.youtube.com/*",
        "https://m.youtube.com/*"
      ],
      "js": [
        "content/extractor.js",
        "content/content.js"
      ],
      "css": [
        "content/content.css"
      ],
      "run_at": "document_idle"
    }
  ],
  "web_accessible_resources": [
    "icons/icon-48.png"
  ],
  "browser_action": {
    "default_title": "Return YouTube Summary",
    "default_popup": "options/panel.html"
  },
  "options_ui": {
    "page": "options/options.html",
    "open_in_tab": true
  },
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png",
    "128": "icons/icon-128.png",
    "512": "icons/icon-512.png"
  }
}