Preview:
const findOverflows = () => {
    const documentWidth = document.documentElement.offsetWidth;

    document.querySelectorAll('*').forEach(element => {
        const box = element.getBoundingClientRect();

        if (box.left < 0 || box.right > documentWidth) {
            console.log(element);
            element.style.border = '1px solid red';
        }
    });
};

// Execute findOverflows to find overflows on the page.
findOverflows();
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