When I use getAttribute to test a value, the result has an upper-case first letter ("Center" instead of "center"). I'm not sure if this is a bug or not (I couldn't find the official rule on this) but it doesn't seem right that the test would fail because I'm only testing for lower-case values. I'm using Mozilla/5.0 (Windows; U; WinNT4.0; en-US; m18) Gecko/20001019 .
Yep, I can't find a statement that says this should be in mixed-case (and this would be a pain for script authors).
According to the second-to-last paragraph in section 1.5.1 in the DOM HTML spec at http://www.w3.org/TR/DOM-Level-2-HTML/html.html#ID-642250288 mozilla does the right thing, it generalizes the attribute values so that they're always the same regardless of how the user sets them. Marking INVALID.
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