chromium/third_party/blink/web_tests/http/tests/xmlviewer/dumpAsText/xul.xml

<!-- If you can see this, this test has failed. -->
<FAIL xmlns:a="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
    <header>This tests that xml viewer is not used when there is an attribute in XUL namespace.</header>
    <box a:attr="value">SUCCESS</box>
</FAIL>