[VE][141] Validator throws "not-unique" error on Case Sensitive IDs

Validating http://providence.org/resources/oregon/test/john/0/id.htm
Error [141]: "ID X already defined"

This paragraph has attribute id="Unique"

This paragraph has attribute id="uNIQUE"

The Validator throws this error:
ID "UNIQUE" already defined.

Shouldn't they be considered not the same ID since the ID attribute is
defined as case sensitive
(http://www.w3.org/TR/html4/struct/global.html#adef-id)?UA's treat them that
way. Why is it an error in the Validator then?

I see nothing that explicitly says they can or cannot be the same id but
capitalized differently; whereas, that the spec says that they are
case-sensitive (http://www.w3.org/TR/html4/struct/global.html#adef-id) seems
to imply that they can match apart from the capitalization.


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