QLMarkdown

Just a stupidly simple QuickLook plugin for Markdown files.

No fancy configuration options, just Github flavored Markdown. But if you insist on modifying the stylesheet, you have full control over that.

Scope of this project

This plugin is a wrapper around swift-markdown (which uses cmark-gfm) to convert markdown into html. No external binary is bundled into the app, everything is compiled directly into the app bundle. Output of the convert is passed, as is, to the preview window. Styling is applied via CSS (customizable) and mimics the GitHub stylesheet.

There wont be any configuration options, nor finetuning which options are active, and no additional features. If you want customizations, you can write your own css file.

Dependencies

https://github.com/swiftlang/swift-markdown (Apache 2.0)
https://github.com/sindresorhus/github-markdown-css (MIT)

Features

Dark Mode
Customizable CSS

How to customize CSS

Right click on the app and select "Show Package Contents"
Go to PlugIns and repeat "Show Package Contents" on the Preview extension.
Copy Contents/Resources/style.css (or markdown.css)
Open ~/Library/Containers/de.relikd.QLMarkdown.Preview/Data/Documents/
Paste the previous file and modify it to your liking

Privacy & Security

Entitlements for the plugin allows access to all files (see App Sandbox Temporary Exception Entitlements). This enables referencing local files (e.g., image, etc).

However, this is also a privacy risk. A malicious QL plugin could send arbitrary file contents to a remote server. Be careful what plugins you install. Especially if it has both entitlements com.apple.security.temporary-exception.files and com.apple.security.network.client. Lucky for you, this open source project is very small and easy to review.