lang(es), xml:lang="mx-es"

Ignore this test. (:lang with xml:lang is not supported)
You can only get meaningful results for this test if :lang works with xml:lang, since it checks a detail with regard to that support.

Test passes if you see green below.

Text

Assertion: When the :lang value uses a single subtag, it will not match against an xml:lang attribute value where that value appears in a different position.

Notes:You can only get meaningful results for this test if :lang works with xml:lang, since it checks a detail with regard to that support. If :lang does not work with xml:lang, the test should show a message "Ignore this test." You should ignore the instructions and test results that follow and mark the results as "not applicable".
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XHTML5

selectors-054
Result summary & related tests