Examine source code of YouTube™ Remaining Time

{
  "manifest_version": 3,
  "version": "1.1.9",
  "name": "YouTube Remaining Time",
  "description": "Does what it says on the tin, with SponsorBlock supported, playback rate adjusted and multiple time formats available.",
  "author": "Nhân Trí",
  "homepage_url": "https://github.com/nhantrichuyenanh/YouTube-Remaining-Time",
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "96": "icons/icon96.png",
    "128": "icons/icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.youtube.com/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_end"
    }
  ],
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "https://sponsor.ajay.app/api/*"
  ],
  "options_ui": {
    "page": "options/options.html",
    "open_in_tab": false
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{3f51429e-c07e-4929-9fd8-b642001fbd41}",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}