Examine source code of Skip Google Redirect

{
  "description": "Skips Google's url redirect page by reading the target address and forwarding there directly. This way Google gets no notification of your click. Works on Youtube as well.",
  "manifest_version": 2,
  "name": "Skip Google Redirect",
  "version": "1.2",
  "homepage_url": "https://github.com/Chandrion/skip-google-redirect",
  "icons": {
    "48": "icons/detour-black-48.png",
    "96": "icons/detour-black-96.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "skip-google-redirect@chandrion.com",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "*://www.google.com/*",
    "*://www.youtube.com/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  }
}