Headlessui is a solid-style Icon from Simple Icons set.

The Headlessui icon shows a tilted rounded square with a bold black border, a diagonal white division, and a black upper section. Drawn in the solid style on a 24px grid so it stays crisp at small sizes. Use it for Headless UI branding, developer documentation, component libraries, design systems, and web interface projects. It belongs to Simple Icons free set in the Brand Logos family.