Examine source code of ScrollMaster Pro

{
  "manifest_version": 3,
  "name": "ScrollMaster Pro",
  "version": "1.0",
  "description": "Customize the appearance and behavior of scroll bars",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "scrollmasterpro@example.com"
    }
  },
  "permissions": [
    "storage",
    "tabs",
    "activeTab"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "css": [
        "content.css"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "options_ui": {
    "page": "options/options.html",
    "open_in_tab": true
  },
  "action": {
    "default_popup": "popup/popup.html",
    "default_icon": {
      "48": "icons/icon-48.png",
      "96": "icons/icon-96.png"
    }
  }
}