startSelecting() {
    if (!shared_utils_1.isBrowser) return;
    window.addEventListener('mouseover', this.elementMouseOver, true);
    window.addEventListener('click', this.elementClicked, true);
    window.addEventListener('mouseout', this.cancelEvent, true);
    window.addEventListener('mouseenter', this.cancelEvent, true);
    window.addEventListener('mouseleave', this.cancelEvent, true);
    window.addEventListener('mousedown', this.cancelEvent, true);
    window.addEventListener('mouseup', this.cancelEvent, true);
  }
Adds event listeners for mouseover and mouseup