The current default implicit ARIA semantic for <aside> is "note". See section 188.8.131.52 Implicit ARIA Semantics .
It is proposed that this be changed to "complementary" for the following reasons:
A. The definition of <aside>  seems more closely aligned to the definition of
the "complementary" role  than it does to the definition of the "note" role , particularly with regard to the element's content still being meaningful when separated from the surrounding content.
B. Firefox/Win and Safari/Mac, the only two browsers currently mapping additional semantics for <aside> to the accessibility APIs, both map it to the "complementary" role, Firefox/Win using an IA2 "xml-roles" object attribute and Safari/Mac an AXSubrole of AXLandmarkComplementary.
C. The HTML to Platform Accessibility APIs Implementation Guide advises that browsers map the <aside> element to the "complementary" role where the accessibility API permits .
I'd be happy to change this. What do other a11y experts say about this?
(In reply to comment #1)
its already been done
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Change Description: No Change
Rationale: Already fixed (thanks Steve!)