Last updated March 18, 2013.

HTML5 is one of five major initiatives Dries has outlined for Drupal 8 development. You can read the initiative announcements here:

Initiative Goals

The main goals of this initiative will be to implement HTML5 in Drupal core in a way that will:

  • Have the most benefit for end users.
  • Enable contributed modules and themes to evolve using HTML5.
  • Allow theme developers to control where to use the new semantic elements, and opt out entirely if they so choose.

We want to ensure we're spending our time implementing features that will directly benefit Drupal's user base the most. As part of this initiative we'll focus mostly on:

  • Adding support for the new form elements to Drupal's Form API.
  • Adding new semantic elements in core templates in an appropriate way.
  • Adding ARIA roles to markup to improve accessibility.
  • Simplifying style and script elements.
  • Ensuring input filters and functions accept HTML5 elements.

Proposals to implement other areas of HTML5 will be considered on a case by case basis.

Initiative Roadmap

Phase 1

  1. Implement a JavaScript fallback for non-supported browsers.
  2. Implement Form API support for new HTML elements.
  3. Re-factor templates and theme functions to use new HTML5 elements.
  4. Add WAI-ARIA roles where possible in markup.
  5. #1174756: Convert <head> markup to HTML5
  6. #732992: Allow filter_xss_admin() to accept HTML5 tags
  7. #1280522: _filter_autop (line break converter) does not recognize html5 block level elements

Phase 2 Possibilities

  1. Rich media handling with <video> and <audio>
  2. Ability to select wrapper HTML tag in the UI for Drupal's building blocks.
  3. Add your proposal here.

Comments

Phase 2, item "3. WYSIWYG editor that uses contenteditable." This is a big issue and isn't directly related to HTML5 markup and techniques. It should be made into its own thing so it doesn't slow the HTML5 initiative down.

I wonder if it makes sense to couple CSS cleaning with markup cleaning. I would love to see a semantic markup that avoids the use of classes as much as possible.
While there's nothing wrong in having "presentational" classes (like "inline" for links), I think it will make themers life easier if we would have less specific elements to style.

If you've got comments on this please do not post them here. Post them on g.d.o. instead:

http://groups.drupal.org/node/157339

What about adding an api for HTML5 storage? Now more and more sites will be using it to improve the way site perform on tablets and other portable devices used on the move, which may not have consistent internet connectivity.

Drupaling...