>If you don't care about conforming, you could theoretically
>use HTML5 elements with any HTML doctype as the browser
>just handles HTML period. (However this might not be true
>for all browsers.)

Graceful error handling allows browsers to ignore undefined elements but render defined elements, e.g., dialog is ignored but its dt/dd elements are displayed. I did the following rough test case with a few HTML5 elements some months ago to see what occurs during error handling: http://www.elementary-group-standards.com/formaldehyde/html-html5-elements.html
Some browsers already render canvas.


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Sean Fraser
http://www.elementary-group-standards.com