Although we might have qualms with the actual usefulness for blind users, I think for a wider spread adoption of BigTree you may consider adding it to the core.
]]>We've been discussing alt tags internally and whether we'd add support for them in the core of BigTree. Where we stand right now is that most alt tags actually impede a blind user's ability to browse a page efficiently (i.e. "Photo of girl in front of a tree" doesn't convey information that's actually useful in the context of a page, but the image itself is nice when visible).
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