Examine source code of Tab Auto Refresh Pro

{
  "version": "0.2.1",
  "manifest_version": 2,
  "offline_enabled": true,
  "name": "Tab Auto Refresh",
  "homepage_url": "https://mybrowseraddon.com/tab-auto-refresh.html",
  "description": "Automatically refresh tabs based on custom time intervals",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "tabs",
    "alarms",
    "storage",
    "notifications"
  ],
  "browser_action": {
    "default_title": "Tab Auto Refresh",
    "default_popup": "data/popup/popup.html",
    "default_icon": {
      "16": "data/icons/16.png",
      "32": "data/icons/32.png",
      "48": "data/icons/48.png",
      "64": "data/icons/64.png"
    }
  },
  "icons": {
    "16": "data/icons/16.png",
    "32": "data/icons/32.png",
    "48": "data/icons/48.png",
    "64": "data/icons/64.png",
    "128": "data/icons/128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{ec7740b8-7a84-408e-b295-ec4a6cc7465a}"
    }
  }
}