chromium/third_party/blink/web_tests/external/wpt/css/css-text-decor/text-shadow/blur.html

<link rel="help" href="https://drafts.csswg.org/css-text-decor-3/#text-shadow-property">
<link rel="mismatch" href="blur-notref.html">
<div style="text-shadow: blue 4px 4px 2px">The shadow should be blurred</div>