Examine source code of RedirectsTree

{
  "manifest_version": 2,
  "name": "RedirectsTree",
  "version": "1.1",
  "description": "Displays the full redirect in chain at browser console when navigating to a new page.",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "webNavigation",
    "tabs",
    "<all_urls>"
  ],
  "browser_action": {
    "default_title": "RedirectsTree"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{6bafb9e4-3807-4b7b-90fa-2af698e0f59a}",
      "strict_min_version": "89.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "icons": {
    "64": "icon64.png",
    "128": "icon128.png"
  }
}