HTML5/HTML4 annotation are scattered all over HTML element pages. They are of dubious help for daily Web development nowadays. We should remove them (and put the info in the spec table of each page). This will lead to clearer pages.
Do you mean the 'Introduced in HTML5' note at the top of a page like for <header>? (For clarifying things I normally provide an example URL in the 'URL' field.) Sebastian  https://developer.mozilla.org/en-US/docs/Web/HTML/Element/header
These line-wide headers but also the HTML5/HTML4 badges in the text: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/textarea As well as the Obsolete in… badges (that will be transformed in obsolete icons).
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