The Theme Handbook is undergoing a significant overhaul in 2024, with a focus on modern block theme development. The project aims to refresh the handbook content and has made substantial progress, publishing or drafting almost two-thirds of the new material.

Adam Lowe has started a video series about building block themes. The first video has a nice walk-through of the Site Editor and overview of block themes. This series looks to be a great resource for people interested in the Site Editor and block themes. Highly recommended.

Here is a good comparison / contrasting look at classic and block themes.

The Theme Team at WordPress org has developed a draft proposal of guidelines for a theme onboarding process. This follows the discussions about the original onboarding wizard from the Ollie Theme that was moved to a plugin.

Block Theme Development – There is a cool plugin called Create Block Theme that allows you to export a new theme or a child theme based on site styles and templates created using the Site Editor.

There have been a couple of improvements to the plugin which include the ability to select, preview, and manage theme fonts, and changes to make it easier to export. These changes are shown in this short video by Jonathan Bossenger.

Block themes get their settings from the theme.json file and classic themes can use them also. Jamie Marsland has published a good resource article about the theme.json file. He does a walk-through of the theme.json file for the Twenty Twenty-Four theme and explains the various sections and settings.

A change was made in WordPress 6.4 to how the main loop is handled in block themes. This might impact blocks that use the query loop.

Creating Block Themes – A section has been added to the Them Handbook on block templating. It shows how the WordPress block template system works, how to build custom templates and parts and include them in a theme.