<!doctype html>
<head>
<style>
#ta {
    background-color: lightGray;
    -webkit-mask: url(resources/rect.svg);
}
</style>
<script>
function test()
{
    // Scroll to the bottom of the text area and remove focus so that painting of outline/focus ring don't affect test result.
    ta.setSelectionRange(ta.value.length, ta.value.length);
    ta.focus();
    ta.blur();
}
</script>
</head>
<body onload="test()">
Test passes if the textarea's gray background and text are masked off to a 10x10 rect.<br>
<textarea id="ta" rows=2>
1
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4
</textarea>
</body>