Examine source code of Smooth Scroller

{
  "manifest_version": 2,
  "name": "Smooth Scroller",
  "version": "1.0.3.2",
  "description": "Effortless hands-free reading: let the page scroll itself at an adjustable speed. Toggle scrolling on and off, tune the rate live, and return to the top instantly. It halts on its own when the page ends.",
  "icons": {
    "32": "assets/icon-32.png",
    "48": "assets/icon-48.png",
    "64": "assets/icon-64.png",
    "96": "assets/icon-96.png",
    "128": "assets/icon-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{4d3ca665-58d3-43b1-8f94-69071518b568}",
      "strict_min_version": "101.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "permissions": [
    "activeTab",
    "storage"
  ],
  "browser_action": {
    "default_title": "Smooth Scroller",
    "default_popup": "app/popup.html",
    "default_icon": {
      "32": "assets/icon-32.png",
      "48": "assets/icon-48.png",
      "64": "assets/icon-64.png"
    }
  }
}