<link rel="help" href="https://drafts.csswg.org/css-contain/#content-visibility">
<link rel="help" href="https://crbug.com/1309693">

<iframe id="target" width=320 height=320></iframe>
<style>
:first-child { content-visibility: hidden; }
html,body,ol { -webkit-column-count: 2; }
</style>