Examine source code of Nature Tab

{
  "name": "Nature Tab",
  "short_name": "Nature Tab",
  "description": "A custom New Tab with beautiful nature wallpapers and backgrounds to make your day! Beautiful backgrounds with every new tab.",
  "version": "1.0.2",
  "icons": {
    "16": "/images/16.png",
    "32": "/images/32.png",
    "48": "/images/64.png",
    "64": "/images/128.png"
  },
  "chrome_url_overrides": {
    "newtab": "html/new_tab_page.html"
  },
  "permissions": [
    "storage",
    "tabs",
    "*://nature-tab.com/*"
  ],
  "manifest_version": 2,
  "background": {
    "scripts": [
      "bg.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{1359c25c-a1e2-4619-a575-7ed25b2c0cc0}"
    }
  }
}