Examine source code of Tab Activity Tracker

{
  "manifest_version": 2,
  "name": "Tab Activity Tracker",
  "version": "1.0",
  "description": "Tracks active tab domain and sends to local backend",
  "permissions": [
    "tabs",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_title": "Tab Tracker"
  },
  "applications": {
    "gecko": {
      "id": "tab-sni-monitor@Ketan.com"
    }
  }
}