Function getFixedPositionOffsetParent

web/static/js/bootstrap.bundle.js:2089–2099

* Finds the first parent of an element that has a transformed property defined * @method * @memberof Popper.Utils * @argument {Element} element * @returns {Element} first transformed parent or documentElement

(element)

   */

  function getFixedPositionOffsetParent(element) {
    // This check is needed to avoid errors in case one of the elements isn't defined for any reason
    if (!element || !element.parentElement || isIE()) {
      return document.documentElement;
    }
    var el = element.parentElement;
    while (el && getStyleComputedProperty(el, 'transform') === 'none') {
      el = el.parentElement;
    }
    return el || document.documentElement;
  }

  /**
   * Computed the boundaries limits and return them