chromium/third_party/blink/web_tests/fast/sub-pixel/sub-pixel-transparency-layer.html

<!DOCTYPE html>
<html>
<head>
<style>
#subPixelContainer {
	width: 100.5px;
	height: 100px;
	position: relative;
}
#subPixelContainer > div {
	position: absolute;
	width: 50px;
	right: 0px;
	height: 50px;
	background-color: red;
	transform: translateZ(0);
}
#test {
	opacity: 0.99;
	position: relative;
	height: 50px;
	top: 0px;
	padding: 0;
	background-color: green;
}
</style>
</head>
<body>
<div>This tests that transparency layers are properly aligned when on sub-pixel offsets. You should see no red.</div>
<div id="subPixelContainer">
	<div><div id="test"></div></div>
</div>