Examine source code of YT Transcript Copier

{
  "manifest_version": 2,
  "name": "YT Transcript Copier",
  "version": "0.2.4",
  "description": "Adds a button to the YouTube player bar to copy transcripts.",
  "permissions": [
    "activeTab",
    "clipboardWrite",
    "https://www.youtube.com/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "yt-transcript-copier@unique-dev-id.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "collects_pii": false,
        "collects_personal_browsing_history": false
      }
    }
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.youtube.com/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ]
}