Examine source code of YT Quick Actions

{
  "manifest_version": 2,
  "name": "__MSG_extName__",
  "description": "__MSG_extDescription__",
  "version": "1.3.1",
  "icons": {
    "16": "icons/16.png",
    "32": "icons/32.png",
    "48": "icons/48.png",
    "128": "icons/128.png"
  },
  "default_locale": "en",
  "permissions": [
    "*://www.youtube.com/*",
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{e34f8313-fac0-4c80-8f91-bb6ac28f4f19}",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "options_ui": {
    "open_in_tab": false,
    "browser_style": false,
    "page": "options.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://www.youtube.com/*"
      ],
      "run_at": "document_start",
      "css": [
        "content-scripts/content.css"
      ],
      "js": [
        "content-scripts/content.js"
      ]
    }
  ]
}