Examine source code of StartGrid - A New Tab

{
  "manifest_version": 3,
  "name": "StartGrid",
  "description": "Customizable Firefox new tab page with widgets",
  "icons": {
    "16": "icons/icon-16.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "startgrid@local",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": [
          "personallyIdentifyingInfo",
          "bookmarksInfo"
        ]
      }
    }
  },
  "chrome_url_overrides": {
    "newtab": "newtab.html"
  },
  "chrome_settings_overrides": {
    "homepage": "newtab.html"
  },
  "permissions": [
    "storage",
    "identity",
    "search"
  ],
  "optional_permissions": [
    "bookmarks"
  ],
  "optional_host_permissions": [
    "http://127.0.0.1/*",
    "https://mail.google.com/*"
  ],
  "version": "1.21.0"
}