Examine source code of Weblings

{
  "manifest_version": 2,
  "name": "Weblings",
  "short_name": "Weblings",
  "version": "3.1",
  "author": "Sean O'Sullivan",
  "description": "Add a little joy to your browser's new tab page.",
  "homepage_url": "https://seanosullivan.co.uk/projects/weblings/",
  "permissions": [
    "storage"
  ],
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "icons": {
    "16": "assets/appicons/16.png",
    "32": "assets/appicons/32.png",
    "64": "assets/appicons/64.png",
    "128": "assets/appicons/128.png",
    "256": "assets/appicons/256.png",
    "512": "assets/appicons/512.png"
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{159a480e-7f70-497d-be75-1b4a8f19a603}"
    }
  }
}