Examine source code of Free Art Tab

{
  "manifest_version": 2,
  "name": "Free Art Tab",
  "version": "1.0.12resigned1",
  "short_name": "Free Art Tab",
  "description": "Free Art Tab with carefully selected artworks from the rich collection of Europeana.",
  "icons": {
    "16": "icon/icon16.png",
    "48": "icon/icon48.png",
    "128": "icon/icon128.png"
  },
  "chrome_url_overrides": {
    "newtab": "stART/stART.html"
  },
  "permissions": [
    "storage",
    "http://www.art-tab.eu/wp-content/"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{d5b60e1d-bc94-4d42-8baf-e24c4505ed48}"
    }
  }
}