dom-helpers/esm/scrollbarSize.js

tiny modular DOM lib for ie9+

import canUseDOM from "./canUseDOM.js";
let size;
export default function scrollbarSize(recalc) {
  if (!size && size !== 0 || recalc) {
    if (canUseDOM) {
      const scrollDiv = document.createElement('div');
      scrollDiv.style.position = 'absolute';
      scrollDiv.style.top = '-9999px';
      scrollDiv.style.width = '50px';
      scrollDiv.style.height = '50px';
      scrollDiv.style.overflow = 'scroll';
      document.body.appendChild(scrollDiv);
      size = scrollDiv.offsetWidth - scrollDiv.clientWidth;
      document.body.removeChild(scrollDiv);
    }
  }
  return size;
}