I sometimes drop down into my Obsidian vault to do some manual file management, and it’s really handy to be able to use Quicklook to preview a file.
QuickLook doesn’t natively support Markdown, but there’s an extension you can install from the Mac App Store that enables support for several file types, including Markdown.
After clicking the link, the Mac App Store tells me “This app is currently not available in your country or region.” Can you share the name of the app you are suggesting?
I know this is an old topic, but I was looking for this currently. I found and installed QLMarkdown [^1]. As of this writing, it was last updated 5aug2024, so it looks like it is currently being updated and maintained. It works well on my macOS 15 (Sequoia) system.