Examine source code of calendar

{
  "manifest_version": 3,
  "name": "Custom New Tab",
  "version": "1.0",
  "description": "Displays custom content in a new tab.",
  "browser_specific_settings": {
    "gecko": {
      "id": "customnewtab@digiform.com",
      "strict_min_version": "91.1.0"
    }
  },
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "permissions": [
    "proxy",
    "tabs"
  ],
  "host_permissions": [
    "https://calendar.bornasan.ir/*"
  ]
}