Changelog — MDViewer

v1.9 — May 6, 2026

Unsaved changes are now clearly visible — edited documents show an Unsaved Changes chip in the viewer.
Review unsaved edits before deciding — you can save, discard, or keep editing without leaving the current document.
Safer closing behavior — closing a tab, a window, or the app now prompts before unsaved changes are lost.

Download v1.9

Auto-reload on external changes — edit a file in another app, and MDViewer picks up the changes automatically. No more stale content after saving in VS Code or Vim.
File-deleted banner — if a file is moved or deleted while open, an orange banner appears with options to save a copy or close the tab. No more silent surprises.
Large file warning — files over 2 MB show a size indicator and two buttons: “Render Anyway” or “Open in Editor.” Prevents accidental freezes on auto-generated dumps.
Wide tables scroll horizontally — tables wider than the content area now get a horizontal scrollbar instead of overflowing into the right edge.
Performance improvements — faster edit/view switching (content updates without full page reload), background Markdown parsing, debounced search, and smoother tab handling.
GFM table escape fix — \| inside table cells is now treated as a literal pipe, matching the GitHub Flavored Markdown spec.

Download v1.8

KaTeX math formulas — inline math with $...$ and display math with $$...$$ now render beautifully. Supports matrices, fractions, Greek letters, and full LaTeX notation.
Improved toast notifications — toasts now include a close button and configurable display duration for a cleaner editing experience.

Download v1.7

QuickLook Preview in Finder — press Space on any .md, .json, or .mermaid file in Finder to see a fully rendered preview without launching the app. Works in column view, icon view, and full-screen Quick Look. The extension installs automatically with MDViewer.
Mermaid contrast fix — diagrams with custom node colors now automatically get dark or light text based on background brightness. No more unreadable labels in dark mode.
Automatic update checks — MDViewer now checks for updates on every launch to make sure you always have the latest version.

Download v1.6

JSON file viewer — open .json files directly in MDViewer. JSON renders as an interactive tree with collapsible nodes, just like browser DevTools. Click [−]/[+] to expand or collapse any level.
JSON Format button — one-click pretty-print that preserves key order and saves to disk.
Syntax highlighting — fenced code blocks now render with color highlighting for 180+ languages (Python, JavaScript, Swift, TypeScript, SQL, and more). GitHub-style theme, adapts to light and dark mode.

Open multiple files and folders — Cmd+O supports multi-select and folder selection. Drag and drop a folder onto MDViewer to open all Markdown files as tabs. Drop files onto an open document too.
Standalone Mermaid files — open .mmd and .mermaid files directly from Finder, drag and drop, or Cmd+O. Diagrams render with the same lightbox, zoom, and dark mode support.
Edit/View toggle button — floating pill button in the top-right corner for quick mode switching. No more hunting through menus.
Online Markdown viewer — getmd.ma/viewer lets you view Markdown files in any browser. Drag and drop, fully private, same rendering as the desktop app.

Search (Cmd+F) — find text across headings, code blocks, tables, and body text. Matches highlight in yellow, current match in orange. Works in both preview and editor modes. Counter shows "2 / 7" and updates live.
Sparkle auto-updates — "Check for Updates" in the app menu. Signed and verified updates delivered through CDN.

Initial release.

Inline editor — double-click any word to edit with the cursor exactly where you clicked. Cmd+S to save, Esc to return to reading.
Git history & diff — browse commit history for any file, click a commit to see a color-coded unified diff with line numbers.
Table of contents — smart sidebar tracks your scroll position, highlights the active heading, click to jump.
Tabbed interface — open multiple files in one window.
Mermaid diagrams — flowcharts, sequence diagrams, ER diagrams render as interactive SVGs. Click to open a full-screen lightbox with zoom and pan.
File tree — browse project files from the sidebar, rooted at your git repository.
Default app for .md — set MDViewer as your default Markdown viewer in one click.
Native macOS app — built with SwiftUI, launches instantly, uses minimal memory. Full GitHub Flavored Markdown support.
Dark mode — follows your system preference automatically.