Examine source code of DNR Domain Redirector

{
  "manifest_version": 3,
  "name": "DNR Domain Redirector",
  "version": "1.0.0",
  "description": "Automatically redirect requests from one or more domains to others",
  "author": "0xa1",
  "homepage_url": "https://github.com/0xa1/firefox-domain-redirector",
  "browser_specific_settings": {
    "gecko": {
      "id": "{8f7e6d5c-4b3a-2c1d-0e9f-8a7b6c5d4e3f}",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png",
    "128": "icons/icon-128.png"
  },
  "action": {
    "default_title": "DNR Domain Redirector",
    "default_popup": "options.html",
    "default_icon": {
      "48": "icons/icon-48.png",
      "96": "icons/icon-96.png",
      "128": "icons/icon-128.png"
    }
  },
  "permissions": [
    "declarativeNetRequest",
    "declarativeNetRequestWithHostAccess",
    "storage"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true,
    "browser_style": false
  }
}