Examine source code of Etherpad Tracker

{
  "name": "Etherpad Tracker",
  "description": "Keep track of your Etherpad pads.",
  "version": "1.0.3",
  "manifest_version": 2,
  "permissions": [
    "storage",
    "history"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "etherpad-tracker@example.com",
      "strict_min_version": "57.0"
    }
  },
  "icons": {
    "16": "images/logo-16.png",
    "32": "images/logo-32.png",
    "48": "images/logo-48.png",
    "128": "images/logo-128.png",
    "192": "images/logo-192.png",
    "512": "images/logo-512.png"
  },
  "browser_action": {
    "default_title": "Etherpad Tracker",
    "default_popup": "index.html",
    "default_icon": {
      "16": "images/logo-16.png",
      "32": "images/logo-32.png",
      "48": "images/logo-48.png",
      "128": "images/logo-128.png",
      "192": "images/logo-192.png",
      "512": "images/logo-512.png"
    }
  }
}