macOS 27.3 adds native Markdown rendering to Quick Look, making .md files easier to read without opening a separate editor or installing an extension. In the operating system’s first developer beta, users can select a Markdown file in Finder and press the Space bar to see a formatted preview.
Quick Look renders elements such as headings, bold text, lists and links in the preview. Previously, this feature was not available natively for Markdown documents.
The change follows other moves by Apple to support Markdown. Notes added Markdown import and export with iOS 26, and iOS 27 introduced Markdown copy and paste. Apple’s developer documentation also says app developers can include SKILL.md files to describe how Siri should handle tasks involving app actions.
Apple released the first developer beta of macOS 27.3 on November 3.
Sources: MacRumors.