LayoutTests/transitions/crossfade-transition.html

<script>
if (window.testRunner) {
    window.testRunner.waitUntilDone();
    window.testRunner.dumpAsText();
}

window.addEventListener("load", function () {
    setTimeout(function () {
        document.body.className = "foo";
        if (window.testRunner) {
            setTimeout(function () {
                window.testRunner.notifyDone();
            }, 50);
        }
    }, 0);
}, false);
</script>
<style>
.a > li,
.a > li p {
  transition: all 0.1s ease;
}

.a > li.b {
  list-style-image: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1 1"><rect width="1" height="1" fill="blue"/></svg>');
}
.foo .a > li.b {
  list-style-image: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1 1"><rect width="1" height="1" fill="red"/></svg>');
}

</style>
<ul class="a">
  <li class="b">
    <p>Test passes if there is no crash</p>
  </li>
</ul>