Examine source code of Random wallpaper

{
  "manifest_version": 3,
  "name": "Random wallpaper",
  "description": "Show a random wallpaper with Bing search on your new tab page",
  "version": "0.6",
  "permissions": [
    "activeTab"
  ],
  "action": {
    "default_icon": {
      "16": "images/icon16.png",
      "48": "images/icon48.png",
      "64": "images/icon64.png",
      "128": "images/icon128.png"
    }
  },
  "icons": {
    "16": "images/icon16.png",
    "48": "images/icon48.png",
    "64": "images/icon64.png",
    "128": "images/icon128.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "chrome_url_overrides": {
    "newtab": "newtab.html"
  },
  "web_accessible_resources": [
    {
      "resources": [
        "newtab.html",
        "newtab.js",
        "images/icon128.png"
      ],
      "matches": [
        "<all_urls>"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "axemedia.com-extension-random-wallpaper@firefox"
    }
  }
}