Examine source code of e-clock

{
  "manifest_version": 3,
  "name": "e-clock",
  "version": "4.2.7",
  "description": "__MSG_i18nShortDescription__",
  "default_locale": "en",
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "icons": {
    "48": "/assets/img/icons/icon48.png",
    "128": "/assets/img/icons/icon128.png"
  },
  "permissions": [
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{1029db62-dbe3-49f5-b4ef-28b10866d58a}"
    }
  }
}