chrome/browser/resources/new_tab_page/untrusted/promo.js

// Copyright 2020 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// TODO(crbug.com/1057147): add tests for chrome-untrusted://new-tab-page files.
document.addEventListener('DOMContentLoaded', () => {
  // Remove the <style> from the raw promo since we want to style the promo
  // ourselves.
  const styleElement = document.querySelector('body > style');
  if (styleElement) {
    styleElement.remove();
  }
  // The <a> elements need to open in the top frame since the promo is loaded
  // in an <iframe>.
  document.body.querySelectorAll('a').forEach(el => {
    if (el.target !== '_blank') {
      el.target = '_top';
    }
  });
  // Inform the embedder that the promo has loaded and can be displayed.
  window.parent.postMessage(
      {frameType: 'promo', messageType: 'loaded'}, 'chrome://new-tab-page');
});