mozilla-release/layout/reftests/first-line/out-of-flow-1a.html

<!DOCTYPE html>
<html>
  <head>
    <title>CSS 2.1 Test Suite: :first-line</title>
    <link rel="author" title="Boris Zbarsky" href="mailto:bzbarsky@mit.edu" />
    <link rel="author" title="Mozilla Corporation" href="http://mozilla.com/" />
    <link rel="help" href="http://www.w3.org/TR/CSS21/selector.html#first-line"/>
    <meta name="flags" content="" />
    <style>
      div { color: green }
      div::first-line { color: red }
    </style>
  </head>
  <body>
    <div><span style="float: left">This should be green</span></div>
  </body>
</html>