Examine source code of Nighty v2

{
  "manifest_version": 2,
  "name": "Nighty",
  "version": "1.0",
  "description": "Automatically switch website interface to dark mode when you open the browser, providing a comfortable experience for the eyes and saving energy.",
  "icons": {
    "48": "icon.png"
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{398d3c1f-5cbe-4de7-8566-6f15db501a8a}"
    }
  }
}