chromium/third_party/blink/web_tests/external/wpt/webvtt/rendering/cues-with-video/processing-model/selectors/cue_function/bold_object/bold_transition_with_timestamp.html

<!DOCTYPE html>
<html class="reftest-wait">
<title>WebVTT rendering, bold object transition with timestamp, ::cue(b:past) selector</title>
<link rel="match" href="bold_transition_with_timestamp-ref.html">
<style>
html { overflow:hidden }
body { margin:0 }
::cue(b) {
    -o-transition: color 9s steps(2, start);
    transition: color 9s steps(2, start);
}
::cue(b:past) {
    color: #00ff00;
}
</style>
<script src="/common/reftest-wait.js"></script>
<video width="320" height="180" autoplay onplaying="this.onplaying = null; this.pause(); this.currentTime = 0.2; takeScreenshotDelayed(1000);">
    <source src="/media/white.webm" type="video/webm">
    <source src="/media/white.mp4" type="video/mp4">
    <track src="../../../support/bold_with_timestamp.vtt">
    <script>
    document.getElementsByTagName('track')[0].track.mode = 'showing';
    </script>
</video>
</html>