Examine source code of YouTube Cleaner

{
  "manifest_version": 3,
  "name": "YouTube Cleaner",
  "version": "1.6",
  "browser_specific_settings": {
    "gecko": {
      "id": "youtube-cleaner@oyaba.dev",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "host_permissions": [
    "*://www.youtube.com/*",
    "*://youtube.com/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://www.youtube.com/*",
        "*://youtube.com/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_start"
    }
  ]
}