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chromium/third_party/blink/web_tests/fast/multicol/one-column-with-break.html 

<!DOCTYPE html>
<html>
    <body style="overflow:hidden;">
        <p>There should be nothing below.</p>
        <div style="-webkit-columns:1; columns:1;">
            <br>
            <div style="break-before:column; -webkit-column-break-before:always;">FAIL</div>
        </div>
    </body>
</html>