I was surprised to learn how core determines if a theme is a block theme or not. In this article by Ryan Welcher talks about the different checks and the ramifications.

Are you interested in block themes? Then you might be interested in this discussion where Nathan Wrigley and Brian Gardner talk about block themes and AI.

The Github repository for the starter theme Underscores _s has been archived.

Have a Block Theme that you like that you’d like to customize? This tutorial shows how to create a theme style variation and use it on another site.

This is a nice look at theme.json and easy ways you can use it for theming.

Last year Anders Noren tweeted a series of steps he takes when creating a new block theme. The steps have been collected into this article which has interesting information about what is involved in creating a block theme, the workflow and some useful tools.

Creating or customizing block themes – this mini-tutorial shows how to enqueue custom styles for individual core blocks. The styles are only loaded when the block is used. The method is straightforward.

Brian Gardner has launched a new premium theme named Open Letter. It is a minimalist block theme.

The Create Block Theme plugin is a free plugin in the WordPress directory. It lets you create a new block theme, clone an existing one, create a child theme, and save user templates and styles to the active theme. This tutorial shows how to use the various plugin features.