Examine source code of Green Timer

{
  "manifest_version": 3,
  "name": "Green Timer & Stopwatch",
  "version": "1.4.0",
  "description": "A sleek #00ff00 themed productivity hub for LeetCode. Features auto-detection, multi-timer tracking, customizable statuses, and deep visual analytics.",
  "permissions": [
    "notifications",
    "alarms",
    "storage",
    "activeTab",
    "scripting",
    "unlimitedStorage"
  ],
  "host_permissions": [
    "*://*.leetcode.com/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "greentimer@nxorg.xchip.in",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  },
  "action": {
    "default_popup": "app.html",
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png",
      "48": "icons/icon-48.png",
      "128": "icons/icon-128.png"
    }
  },
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  }
}