How to use the @fullcalendar/core.removeElement function in @fullcalendar/core

DayGridEventRenderer.prototype.detachSegs = function () {
        var rowStructs = this.rowStructs || [];
        var rowStruct;
        while ((rowStruct = rowStructs.pop())) {
            removeElement(rowStruct.tbodyEl);
        }
        this.rowStructs = null;
    };
    // Uses the given events array to generate  elements that should be appended to each row's content skeleton.

Popover.prototype.destroy = function () {
        this.hide();
        if (this.el) {
            removeElement(this.el);
            this.el = null;
        }
        document.removeEventListener('mousedown', this.documentMousedown);
    };
    // Positions the popover optimally, using the top/left/right options

TimeGrid.prototype.unrenderContentSkeleton = function () {
        removeElement(this.contentSkeletonEl);
    };
    // Given a flat array of segments, return an array of sub-arrays, grouped by each segment's col

detachSegs(segs: Seg[]) {
    for (let seg of segs) {
      removeElement(seg.el)
    }
  }

ElementMirror.prototype.cleanup = function () {
        if (this.mirrorEl) {
            removeElement(this.mirrorEl);
            this.mirrorEl = null;
        }
        this.sourceEl = null;
    };
    ElementMirror.prototype.updateElPosition = function () {

unrenderContentSkeleton() {
    removeElement(this.contentSkeletonEl)
  }

segs.forEach(function(seg) {
      removeElement(seg.el)
    })

cleanup() {
    if (this.mirrorEl) {
      removeElement(this.mirrorEl)
      this.mirrorEl = null
    }

    this.sourceEl = null
  }