Install the app and run it. This will register the availability of the app’s QuickLook extensions, Previewer and Thumbnailer. You can now quit the app: just click OK:
Using QuickLook in Finder — select a Markdown file (
.markdown, for example) and press space — will pop up a rendered image of file:
You can disable or re-enable Previewer and Thumbnailer in System Preferences > Extensions:
For some background information on how Catalina delivers QuickLook previews, please see this blog post.
From version 1.3.0, PreviewMarkdown will optionally preview YAML front matter at the start of your Markdown files. YAML is often used this way to hold metadata that will be read by static website generators when they read the Markdown content for page rendering.
The app’s Preferences panel allows you to adjust some of the key elements of the preview:
Choose your preferred text size — headings are scaled up from this value in even steps — using the slider, then pick the fonts you want regular text and code to be presented in. You can also choose each font’s style:
Choose your preferred heading and code colours by clicking the appropriate colour well to pop up macOS’ colour picker. As you make your colour selection, the colour well will be updated:
Click Save to apply your choices.
Changing these settings will affect previews immediately, but may not affect thumbnails until you open a folder that has not been previously opened during the current login session. Thumbnails are always presented dark-on-light, even under macOS’ Dark Mode. This is a Finder convention.
You can use the in-app UI to submit feedback or contact me. Just click in the Send Feedback button in the main window, or select Report a Bug… from the Help menu:
If it appears that either Previewer or Thumbnailer are not working after you have run the host app, please log out of your Mac and then log back in.
Some applications which can edit Markdown files may register a non-standard, proprietary Uniform Type Identifier (UTI) for Markdown files. PreviewMarkdown may not be aware of these UTIs and therefore may not be able to preview and thumbnail these files on your system. If you encounter this issue — typically, previews of markdown files will show the raw formatting text — please run utitool to see your system’s registered Markdown file UTI. This UTI will automatically be included in any message you send using PreviewMarkdown’s feedback facility.
If you have found PreviewMarkdown to be useful, please consider writing a positive review on the Mac App Store, or simply give it a rating.
PreviewMarkdown makes use of code from the following sources:
You can view PreviewMarkdown’s source code at GitHub.
string index out of rangein SwiftyMarkdown).