Cómo personalizar el administrador Jumpseller con Tampermonkey

// ==UserScript==
// @name         Jumpseller — Order units (visual)
// @namespace    jumpseller.local.order-units
// @version      0.3.0
// @description  Suma las cantidades ya renderizadas del pedido. Solo visual; no guarda ni envía datos.
// @match        https://*.jumpseller.com/admin/*/orders/*
// @match        https://*.jumpseller.com/admin/orders/*
// @match        https://*.jumpseller.com/admin/*/orders-v2/*
// @match        https://*.jumpseller.com/admin/orders-v2/*
// @run-at       document-idle
// @grant        none
// @noframes
// ==/UserScript==
/* Local visual helper for Jumpseller admin order pages (orders and orders-v2) only.
 * No network calls, credentials, storage or order/theme writes.
 * Bundles/packs are unsupported: parent/component rows can be double-counted.
 * If the admin markup changes, disable the script and request a review.
 */
(() => {
  'use strict';
  if (!/^([a-z0-9]+(?:-[a-z0-9]+)*)\.jumpseller\.com$/i.test(location.hostname) || window.top !== window.self) return;
  // Supports both order screens: /admin/<locale>/orders/edit/<ID> and /admin/<locale>/orders-v2/edit/<ID>.
  if (location.protocol !== 'https:' || !/^\/admin\/(?:[a-z]{2}(?:-[a-z]{2})?\/)?orders(?:-v2)?(?:\/|$)/i.test(location.pathname)) return;
  const ROUTE = /^\/admin\/(?:([a-z]{2})(?:-[a-z]{2})?\/)?orders(?:-v2)?\/edit\/(\d+)\/?$/i;
  const KEY = '__jumpsellerVisualOrderUnits';
  const ID = 'jumpseller-visual-order-units';
  window[KEY]?.stop?.();
  let scheduled = null;
  let stopped = false;
  const routeId = () => location.pathname.match(ROUTE)?.[2] || null;
  const SPANISH = ['es', 'cl', 'mx', 'ar', 'co', 'pe', 'uy', 'ec', 'bo', 'py', 've', 'cr', 'gt', 'do', 'pa', 'sv', 'hn', 'ni'];
  const loc = (location.pathname.match(ROUTE)?.[1] || document.documentElement?.lang || 'en').slice(0, 2).toLowerCase();
  const labels = ['pt', 'br'].includes(loc)
    ? ['Total de unidades', 'linhas de produto', 'Cálculo local; não é guardado. Bundles não suportados.']
    : SPANISH.includes(loc)
      ? ['Total de unidades', 'líneas de producto', 'Cálculo local; no se guarda. Bundles no soportados.']
      : ['Total units', 'product lines', 'Local calculation; not saved. Bundles unsupported.'];
  function remove() { document.getElementById(ID)?.remove(); }
  function directText(element) {
    return Array.from(element.childNodes).filter(n => n.nodeType === 3).map(n => n.textContent).join('');
  }
  function readTable(table) {
    let units = 0, lines = 0;
    for (const row of table.querySelectorAll('tbody > tr')) {
      // Product rows show "$price x qty" in a div; subtotal/shipping/total rows don't.
      // The product image is not required: it can be missing and its markup differs between screens.
      const price = row.querySelector('td > div.tabular-nums');
      if (!price) continue;
      const match = directText(price).trim().match(/\s[x×]\s*(\d+)\s*$/u);
      if (!match) throw Error('Unrecognized quantity');
      const qty = Number(match[1]);
      if (!Number.isSafeInteger(qty) || qty < 0 || !Number.isSafeInteger(units + qty)) throw Error('Invalid quantity');
      units += qty; lines++;
    }
    if (!lines) throw Error('No product rows');
    return { units, lines };
  }
  function update() {
    scheduled = null;
    if (stopped) return;
    const id = routeId();
    if (!id) { remove(); return; }
    // Show a total only when the displayed order matches the current page.
    const headings = Array.from(document.querySelectorAll('.text-xl.font-normal'))
      .filter(e => new RegExp('#\\s*' + id + '\\s*$').test(e.textContent.trim()));
    if (headings.length !== 1) { remove(); return; }
    const heading = headings[0];
    const root = heading.parentElement;
    const tables = Array.from(root.querySelectorAll('table.w-full.border-collapse'))
      .filter(t => t.querySelector('tbody > tr > td > div.tabular-nums'));
    if (tables.length !== 1) { remove(); return; }
    let count;
    try { count = readTable(tables[0]); }
    catch (_) { remove(); return; } // Fail closed: no misleading partial count.
    let badge = document.getElementById(ID);
    if (!badge) {
      badge = document.createElement('div');
      badge.id = ID;
      badge.setAttribute('role', 'status');
      badge.setAttribute('aria-live', 'polite');
      badge.style.cssText = 'margin:8px 0;padding:10px 14px;border:1px solid #d1d5db;border-radius:6px;background:#f8fafc;color:#111827;font-size:15px;font-weight:600';
      heading.insertAdjacentElement('afterend', badge);
    } else if (badge.previousElementSibling !== heading) {
      heading.insertAdjacentElement('afterend', badge);
    }
    const label = `${labels[0]}: ${count.units}`;
    if (badge.textContent !== label) badge.textContent = label;
    const title = `#${id} · ${count.lines} ${labels[1]} · ${labels[2]}`;
    if (badge.title !== title) badge.title = title;
  }
  function schedule() {
    if (!stopped && scheduled === null) scheduled = setTimeout(update, 80);
  }
  const observer = new MutationObserver(schedule);
  observer.observe(document.body, { childList: true, subtree: true, characterData: true });
  const interval = setInterval(schedule, 1000); // URL changes with no DOM event.
  const handle = {
    stop() {
      stopped = true;
      observer.disconnect();
      clearTimeout(scheduled);
      clearInterval(interval);
      remove();
      if (window[KEY] === handle) delete window[KEY];
    }
  };
  window[KEY] = handle;
  update();
})();