third_party/blink/web_tests/fast/css/hover-leftmost-quirks.html

<!-- quirks mode -->
<script src="../../resources/js-test.js"></script>
<style>
:hover#t1,
:hover.c2,
:hover[a3] { background-color: green }
</style>
<div id="t1">Green background when hovered</div>
<div id="t2" class="c2">Green background when hovered</div>
<div id="t3" a3>Green background when hovered</div>
<script>
description("Quirks mode - simple selectors right of :hover");

function moveTo(element) {
    eventSender.mouseMoveTo(element.offsetLeft + 1,  element.offsetTop + 1);
}

var transparent = "rgba(0, 0, 0, 0)";
var green = "rgb(0, 128, 0)";

shouldBeDefined("window.eventSender");

shouldBe("getComputedStyle(t1).backgroundColor", "transparent");
moveTo(t1);
shouldBe("getComputedStyle(t1).backgroundColor", "green");

shouldBe("getComputedStyle(t2).backgroundColor", "transparent");
moveTo(t2);
shouldBe("getComputedStyle(t2).backgroundColor", "green");

shouldBe("getComputedStyle(t3).backgroundColor", "transparent");
moveTo(t3);
shouldBe("getComputedStyle(t3).backgroundColor", "green");
</script>