Examine source code of Smart Dial

{
  "manifest_version": 2,
  "name": "Smart Dial",
  "version": "1.0",
  "description": "Overrides the new tab page to display your bookmarks in a beautiful masonry grid with high-resolution images.",
  "browser_specific_settings": {
    "gecko": {
      "id": "@smart-dial",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "bookmarksInfo",
          "browsingActivity",
          "websiteContent"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  },
  "permissions": [
    "bookmarks",
    "storage",
    "tabs",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "chrome_url_overrides": {
    "newtab": "newtab.html"
  },
  "browser_action": {
    "default_icon": "icons/icon.png",
    "default_popup": "popup.html"
  },
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  }
}