root-element-background-image-transparency-001-ref.html

<!DOCTYPE html>
<html>
  <head>
    <title>CSS Reftest Reference</title>
    <link rel="author" title="Matt Woodrow" href="mailto:[email protected]">
    <style>
      html {
        background-color: white;
      }
      body {
        /* The default 8px margin makes the background not line up exactly */
        margin: 0;
        background: url(support/transform-triangle-left.svg) top left;
        opacity: 0.5;
        height: 100vh;
      }
    </style>
  </head>
  <body>
  </body>
</html>

chromium/third_party/blink/web_tests/external/wpt/css/compositing/root-element-background-image-transparency-001-ref.html