<!DOCTYPE html>
<style>
thead {
    break-inside: avoid;
}
</style>
<p>crbug.com/720620: Break-inside avoid content doesn't overlap with repeating headers.</p>
<div style="columns:2; line-height:20px; column-fill:auto; height:100px; orphans:1; widows:1; background:yellow;">
    <table cellspacing="0" cellpadding="0" style="background:pink;">
        <thead>
            <tr>
                <th>repeated header</th>
            </tr>
        </thead>
        <tbody>
            <tr>
                <td>
                    <div>
                        line1<br>
                        line2<br>
                        line3<br>
                        <div style="break-inside:avoid;">
                            line4<br>
                            line5<br>
                            line6<br>
                        </div>
                    </div>
                </td>
            </tr>
        </tbody>
    </table>
</div>