Examine source code of GATE-Calculator

{
  "manifest_version": 2,
  "name": "GATE Calculator",
  "version": "1.3",
  "description": "An on-screen GATE exam calculator replicating the official scientific calculator interface.",
  "icons": {
    "16": "icons/icon.png",
    "32": "icons/icon.png",
    "48": "icons/icon.png",
    "128": "icons/icon.png"
  },
  "permissions": [
    "storage"
  ],
  "browser_action": {
    "default_title": "GATE Calculator",
    "default_icon": {
      "16": "icons/icon.png",
      "32": "icons/icon.png",
      "48": "icons/icon.png",
      "128": "icons/icon.png"
    },
    "default_popup": "index.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{4672b986-79bc-4686-afce-62e25614a5a9}"
    }
  }
}