Examine source code of archive.today Redirector

{
  "manifest_version": 2,
  "name": "Archive Redirector",
  "version": "1.0",
  "description": "Redirects archive.today URLs to archive.is",
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{1e8b10b3-fa84-4686-9b48-f30010cd09b5}"
    }
  }
}