text-spacing-trim-space-all-001-ref.html

<!DOCTYPE html>
<meta charset="utf-8">
<style>
@font-face {
  font-family: halt-font;
  src: url('/fonts/noto/cjk/NotoSansCJKjp-Regular-subset-halt.otf');
}
#container {
  font-family: halt-font;
  font-size: 20px;
  text-spacing-trim: space-all;
  width: 4em;
}
#container > div > span {
  background: black;
}
</style>
<div id="container">
  <div><span>国国国国国国国国国国</span></div>
</div>

chromium/third_party/blink/web_tests/external/wpt/css/css-text/text-spacing-trim/text-spacing-trim-space-all-001-ref.html