The clinic is getting busy with more HTML5 ailments. This week, we’ll cover server-side validation, immutable images with <canvas>, retrieving drawn objects from a <canvas>, creating custom tags, the role attribute, and the effects of <hgroup> on SEO.

We’re back with another round of patient questions about HTML5. In this article, we’ll discuss using multiple <h1>s, audio codecs, microformats, post bylines, and the <time> element.