The macOS 27.3 developer beta is packed with headline features. Safari gets Vertical Tabs and Adaptive Dark Mode, Siri AI picks up new skills, and developers get a fresh set of tools. There’s another change that hasn’t gotten much attention, though it’s the one I’ll probably use the most.
Quick Look now supports Markdown. I do all my writing in Markdown, so seeing a properly formatted preview with a tap of the Space bar will make my life much easier.
What is Markdown?
If you have never heard of it, Markdown is a simple text formatting language that John Gruber introduced in 2004. It lets you add headings, bold text, lists, and links with a few simple characters, and converts your plain text into clean HTML.
Today, you’ll find Markdown everywhere, from software documentation to blogs and online publications. AI agents have given it another use, as many rely on .md files to keep their instructions and context.
What changes in Quick Look?
Until now, Quick Look showed .md files as raw text, hashtags and asterisks included. Starting with macOS 27.3 beta 1, Quick Look renders these files with proper formatting, so you see the finished result without opening a separate app.
Apple has been embracing Markdown across its platforms. Apple Notes can already import and export Markdown files, and as Federico Viticci pointed out, Siri AI’s new app skills feature uses Markdown-based SKILL.md files to help Siri handle complex tasks inside apps.
I’ll happily take this improvement. Checking a draft’s formatting without launching another app is exactly the kind of small change I appreciate.