ionic-framework/core/src/utils/status-tap.ts

import { readTask, writeTask } from '@stencil/core';

import { componentOnReady } from './helpers';

export const startStatusTap = () => {
  const win = window;
  win.addEventListener('statusTap', () => {
    readTask(() => {
      const width = win.innerWidth;
      const height = win.innerHeight;
      const el = document.elementFromPoint(width / 2, height / 2) as (Element | null);
      if (!el) {
        return;
      }
      const contentEl = el.closest('ion-content');
      if (contentEl) {
        new Promise(resolve => componentOnReady(contentEl, resolve)).then(() => {
          writeTask(async () => {

            /**
             * If scrolling and user taps status bar,
             * only calling scrollToTop is not enough
             * as engines like WebKit will jump the
             * scroll position back down and complete
             * any in-progress momentum scrolling.
             */
            contentEl.style.setProperty('--overflow', 'hidden');

            await contentEl.scrollToTop(300);

            contentEl.style.removeProperty('--overflow');
          });
        });
      }
    });
  });
};