Two simultaneously events in Javascript [closed]

I have two simultaneously events

document.addEventListener("DOMContentLoaded", function() {
 Array.from(popUps).forEach((el, index) => {
  const listener = () => {
        let trParent = el.parentNode;
        popUpsChilds[index].classList.toggle("show");
        tableThMain.classList.toggle("toggle-goods-popup-for-head");
        el.classList.toggle("toggle-goods-popup-for-cell");
        trParent.classList.toggle("tr-height");
       
    }

    el.addEventListener("mouseover", listener, false);
    el.addEventListener("mouseout", listener, false);
 });
});

Sometimes, when page may be is not loaded completely, “mouseout” couldn’t happen. But i’ve putted DOMContentLoaded event.
What should I do with it?