How to check if a HTML document is empty via JavaScript without causing layout/reflow?

Need to check if an HTML div is empty and contains no text and no child elements as such inside it – a black page only.

e.g

function isPageEmpty(page) {
    const paragraphNodes = page.querySelectorAll(".paragraph");
    if ((paragraphNodes[0].children[0]).innerText !== "") {
      return false;
    }

    return true;
}

What would be the best way to do it, current code causing re calculation of styles?

Open for suggestion and new ideas.