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chromium/third_party/blink/web_tests/fast/multicol/scrollable-basic.html 

<!DOCTYPE html>
<p>The word "PASS" should be seen below.</p>
<div id="scrollable" style="overflow:hidden; columns:1; column-gap:0; width:100px; height:100px;">
    <div style="height:900px;"></div>
    PASS
</div>
<script>
    document.getElementById("scrollable").scrollLeft = 10000;
</script>