Everyone keeps getting this wrong. Subtitles are not headings! They don't introduce new sections of content!
#bootstrappic.twitter.com/hS1CTeaeQa
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Looks like Chrome recognizes the hgroup element (in user agent styles to display as block). But I'm doubtful it has any impact on assistive technologies. Tested in Voiceover and the second heading inside hgroup is not removed from the outline.
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