Examine source code of Replace New Window Start Page

{
  "manifest_version": 2,
  "name": "Replace New Window Startup Page",
  "version": "1.0.0",
  "author": "Daniel Hubmann",
  "homepage_url": "https://github.com/hubisan/replace-new-window-startup-page",
  "browser_specific_settings": {
    "gecko": {
      "id": "replace-new-window-startup-page@hubisan.apps",
      "strict_min_version": "109.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "description": "Replaces the new window startup page if it matches a specific URL. This is useful when the IT department forces a specific URL as the new window startup page.",
  "permissions": [
    "tabs",
    "storage",
    "webRequest",
    "webRequestBlocking",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "src/background.js"
    ]
  },
  "options_ui": {
    "page": "src/options/options.html",
    "browser_style": true
  },
  "icons": {
    "48": "assets/icons/icon48.png",
    "96": "assets/icons/icon96.png"
  }
}