Examine source code of URLCleaner

{
  "description": "Cleaning URLs from trackers and other toxic overloads. For now, gmail, snip.ly and fbclid, utm_",
  "manifest_version": 2,
  "name": "URLCleaner",
  "version": "0.8",
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "urlcleaner.js"
    ]
  },
  "icons": {
    "48": "icons/url-48.png"
  }
}