chromium/third_party/blink/web_tests/external/wpt/css/css-writing-modes/text-combine-upright-rtl-001-ref.html

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8"/>
<title>CSS Writing Modes reference</title>

<style>
div {
  writing-mode: vertical-rl;
  font: 32px serif;
  margin: 1em;
  padding: .25em;
  border: 1px solid gray;
}
span {
  text-combine-upright: all;
}
</style>

Both boxes should render the same:

<div>
<p>foo<span>1</span>bar</p>
<p>foo<span>12</span>bar</p>
<p>foo<span>123</span>bar</p>
<p>foo<span>1234</span>bar</p>
</div>

<div>
<p>foo<span>1</span>bar</p>
<p>foo<span>12</span>bar</p>
<p>foo<span>123</span>bar</p>
<p>foo<span>1234</span>bar</p>
</div>