A Markdown file rendered by the MarkdownView plugin in Double Commander on macOS — showing KaTeX math, a Mermaid flowchart, syntax-highlighted code, and tables — Real output: `.md` rendered in Double Commander's viewer — KaTeX math, a Mermaid diagram, highlighted code, and tables, all from one plugin.

Two small, fast, native plugins that fill real gaps in Double Commander on macOS. Each is a universal binary (Apple Silicon + Intel), built with no third-party libraries and no network access, and tested against the real built artifact. They use the Total Commander plugin ABI, so they load straight into Double Commander.

MarkdownView WLX · lister

A Markdown preview/viewer plugin for Double Commander on macOS. Select any .md file and press F3 — it opens beautifully rendered instead of as raw text (as shown above), and you can switch back to plain text any time.

GitHub-style rendering, syntax highlighting, tables & task lists (GitHub Flavored Markdown)
Mermaid diagrams and KaTeX math (loaded only for files that use them)
Automatic light/dark theming; relative images; scroll position preserved across files
Content is sanitized (DOMPurify) before rendering — safe on untrusted files

MediaInfo WDX · content

See image and video resolution (and more) in a Double Commander column. The bundled QuickLook preview never shows pixel dimensions; this content plugin adds them — plus durations, codecs, and PDF page counts — right in the file listing and tooltips. One adaptive Summary column covers every file type:

IMG_0024.jpg 3.6 M 3024 × 4032 MVI_0044.avi 3.9 M 640 × 480 · 0:04 song.m4a 5.1 M 3:45 report.pdf 820 K 14 pages

Images: dimensions, megapixels, DPI, bit depth (via ImageIO — header read only)
Audio/video: duration, bitrate, sample rate, channels, codecs (AVFoundation)
AVI: resolution, duration, frame rate (self-contained RIFF parser)
PDF: page count. Every field is also available as its own sortable column.

Install

Download the latest release bundle (no Xcode needed), unzip, quit Double Commander, then run the installer:

./install.sh

Or build from source — see each plugin's README. Double Commander is ad-hoc signed with no library validation, so the ad-hoc-signed plugins load cleanly.

Built in the open

This is also a worked example of native macOS plugin development: prove the platform mechanism with a focused test before writing the feature, and fix root causes. The wiki documents the WLX/WDX plugin ABIs, and these write-ups dig into two instructive, host-dependent bugs:

Why WKWebView swallows the Escape key in Double Commander — and the fix (a Lazarus/LCL host dispatches shortcuts via NSApplication -sendEvent:).
Floating-point exception traps crash native plugins in Double Commander — why ImageIO math is fatal under Free Pascal's FP-exception traps, and how to mask it.