chromium/third_party/blink/web_tests/external/wpt/css/filter-effects/filters-opacity-002-test.html

<!DOCTYPE html>
<html>
<head>
    <title>CSS Filter Test: Test opacity shorthand with value 0</title>
    <link rel="author" title="Naohiro Nakajima" href="mailto:[email protected]">
    <link rel="reviewer" title="Dirk Schulze" href="mailto:[email protected]">
    <link rel="help" href="http://www.w3.org/TR/filter-effects-1/#FilterProperty">
    <link rel="help" href="https://www.w3.org/TR/filter-effects-1/#funcdef-filter-opacity">
    <link rel="match" href="reference/filters-opacity-002-ref.html">
    <meta name="assert" content="CSS opacity filter will apply a transparency to the div element.
    Since opacity is 0, it has affect on the div to be transparent.">
    <style type="text/css">

        .box1{
            width:200px;
            height: 200px;
            background: green;
        }
       .box2{
            width: 200px;
            height: 200px;
            background: red;
            filter: opacity(0);
        }

    </style>
</head>
<body>
<p>Test filter opacity CSS shorthand. You should see a green box.</p>
<!-- PAGE CONTENT -->
    <div class="box1"></div>
    <div class="box2"></div>

</body>
</html>