When WordPress 6.3 bundled the Details block, I was excited. Really! I’m a theme author, so I always get excited when a new block lands in Core. Because that means I get to play with it—see what it does and how it works, and, best of all, figure out new ways to put it to work.
And I’ve been anticipating this one for years.
The Details block combines two HTML elements: <details> and <summary>. It is an HTML-native way to show and hide content: the summary part is a title that hides the details until your user clicks on it to trigger a reveal of the details.
Now, by default, it doesn’t look that impressive: