Examine source code of IP Subnet Calculator

{
  "manifest_version": 2,
  "name": "IP Subnet Calculator",
  "version": "1.2",
  "description": "Fast IP Subnet Calculator - Calculates network, broadcast, host range, mask and more. Works for IPv4.",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "@IPCalc-by-Sibil",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "browser_action": {
    "default_title": "IP Subnet Calculator",
    "default_icon": "icons/icon-48.png",
    "default_popup": "popup.html"
  },
  "permissions": [
    "storage"
  ]
}