Examine source code of Autokiosko_screen

{
  "manifest_version": 3,
  "name": "Autokiosko_screen",
  "version": "3.0",
  "description": "Abre todas las ventanas de Firefox en modo kiosko",
  "action": {
    "default_icon": {
      "64": "icons/Autokiosko_screen64x64.png",
      "128": "icons/Autokiosko_screen128x128.png"
    }
  },
  "background": {
    "scripts": [
      "startup.js"
    ]
  },
  "host_permissions": [
    "<all_urls>"
  ],
  "icons": {
    "64": "icons/Autokiosko_screen64x64.png",
    "128": "icons/Autokiosko_screen128x128.png"
  },
  "homepage_url": "https://github.com/tonyway/Autokiosko_screen",
  "browser_specific_settings": {
    "gecko": {
      "id": "tonyway@tonyway.com.ve",
      "strict_min_version": "93.0"
    }
  }
}