Examine source code of Quick Timer Pro

{
  "manifest_version": 2,
  "name": "Quick Timer Pro",
  "version": "2.0.0",
  "description": "Timer premium — multi-timer, suara, label, history, keyboard shortcut",
  "permissions": [
    "alarms",
    "storage",
    "notifications"
  ],
  "browser_action": {
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png",
      "48": "icons/icon-48.png",
      "96": "icons/icon-96.png"
    },
    "default_title": "Quick Timer Pro",
    "default_popup": "popup.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "commands": {
    "quick-1h": {
      "suggested_key": {
        "default": "Ctrl+Shift+T"
      },
      "description": "Timer 1 Jam"
    },
    "quick-30m": {
      "suggested_key": {
        "default": "Ctrl+Shift+Y"
      },
      "description": "Timer 30 Menit"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "quick-timer-pro@extension",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  }
}