Wie zentriere ich ein Popup-Fenster im Browser?

<code class="javascript">const popupCenter = ({ url, title, w, h }) => {
    // Determine the positions based on screen resolution
    const dualScreenLeft = window.screenLeft || window.screenX;
    const dualScreenTop = window.screenTop || window.screenY;

    const width = window.innerWidth || document.documentElement.clientWidth || screen.width;
    const height = window.innerHeight || document.documentElement.clientHeight || screen.height;

    // Adjust for system zoom
    const systemZoom = width / window.screen.availWidth;

    // Calculate the centered coordinates
    const left = (width - w) / 2 / systemZoom + dualScreenLeft;
    const top = (height - h) / 2 / systemZoom + dualScreenTop;

    // Open the popup window with the calculated dimensions and positioning
    const newWindow = window.open(url, title,
        `
        scrollbars=yes,
        width=${w / systemZoom},
        height=${h / systemZoom},
        top=${top},
        left=${left}
        `
    );

    if (window.focus) newWindow.focus();
};</code>

<code class="javascript">popupCenter({ url: 'http://www.xtf.dk', title: 'xtf', w: 900, h: 500 }); </code>