Examine source code of Private URLs

{
  "manifest_version": 2,
  "name": "Private URLs",
  "version": "0.1.1resigned1",
  "author": "Jon Dufresne",
  "description": "Clean and rewrite URLs to their final destination",
  "background": {
    "scripts": [
      "privateurls.js"
    ]
  },
  "permissions": [
    "<all_urls>",
    "webRequest",
    "webRequestBlocking"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{9522af3c-d965-4740-b39d-25b6246f4ccb}"
    }
  }
}