chromium/third_party/blink/web_tests/external/wpt/css/css-flexbox/stretching-orthogonal-flows.html

<!DOCTYPE html>
<title>CSS Flexbox: Stretch alignment for children with orthogonal flows</title>
<link rel="help" href="https://drafts.csswg.org/css-flexbox/#flex-property">
<link rel="help" href="https://drafts.csswg.org/css-flexbox/#align-items-property">
<link rel="match" href="reference/stretching-orthogonal-flows-ref.html">
<link href="support/flexbox.css" rel="stylesheet">
<meta name="assert" content="The test ensures that the stretch alignment of flex items work
similarly with both parallel and orthogonal flows.">

<p>You should see no red.</p>

<div class="flexbox column align-items-stretch" style="background-color: red;">
  <div style="background-color: green; height: 20px;"></div>
  <div style="writing-mode: vertical-lr; background-color: green; height: 20px;"></div>
</div>