[lang="es"], lang="mx-es"

Ignore this test. (lang= with lang attribute is not supported)
You can only get meaningful results for this test if the lang= selector works with the lang attribute, 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 attribute value where it appears in a different position.

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HTML5

selectors-038
Result summary & related tests