Examine source code of VTOP Dark Mode

{
  "manifest_version": 3,
  "name": "VTOP Dark Mode",
  "version": "1.1",
  "description": "Makes VTOP dark mode",
  "content_scripts": [
    {
      "matches": [
        "https://vtop.vit.ac.in/*",
        "https://vtopreg.vit.ac.in/*",
        "https://moovit.vit.ac.in/*"
      ],
      "js": [
        "dark_mode.js"
      ]
    }
  ],
  "action": {
    "default_icon": {
      "48": "icons/btop.png"
    }
  },
  "icons": {
    "48": "icons/btop.png"
  },
  "host_permissions": [
    "https://vtop.vit.ac.in/*",
    "https://vtopreg.vit.ac.in/*",
    "https://moovit.vit.ac.in/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "vtop-dark-mode@your-domain.com"
    }
  }
}