Mark O Down is not a Markdown editor with a preview pane – the document is the preview. You edit
headings, bold text, lists, links, images, tables and badges directly, and the file on disk stays
clean Markdown.

What’s new in 0.2.0

• 🔍 Find & replace – Ctrl+F / Ctrl+H, all matches highlighted, match case, whole word,
  regular expressions with $1 groups, Replace all as a single undo step.
• 🛡️ No more lost work – changes made by other programs (git pull, another editor, cloud sync)
  are detected and never overwritten without asking; after a crash or power loss your unsaved
  changes are offered for recovery.
• 🌐 Open HTML files – converted to Markdown; a dialog first lists exactly what Markdown can’t keep.
• 🕘 Recently opened files in the Open menu.
• 🔎 Zoom – Ctrl+Mouse wheel, Ctrl+Plus / Ctrl+Minus / Ctrl+0, 50–300 %.
• ⌨️ Dialogs keep the keyboard focus (Tab no longer jumps into the document behind them), plus
  security, performance and bug fixes – see the changelog.

Features

• True WYSIWYG for CommonMark + GitHub Flavored Markdown: headings, bold/italic/strikethrough,
  inline code, code blocks, bullet/numbered/task lists, quotes, links, images, horizontal rules, tables.
• Lossless round-trip – open → save without edits is byte-identical. When you edit, only the
  changed blocks are rewritten, in their original style (* vs - bullets, __bold__ vs **bold**,
  ~~~ vs ``` fences, compact |---| vs aligned tables …). BOM and CRLF/LF line endings are kept.
• Everything else is preserved – HTML, footnotes, front matter and other constructs the editor
  doesn’t edit visually are kept verbatim and shown as editable raw blocks.
• README-friendly HTML – <div align="center">, <br> and <img width="…"> / <a><img></a>
  logos are rendered and editable.
• Badge & icon picker – shields.io, badgen.net,
  forthebadge.com, all Simple Icons, your own images.
  Sources and templates are configurable (badges.json), icon lists are cached for offline use.
• Emoji & symbol picker – every Unicode emoji and ~9,700 symbols with English and German names
  and keywords. Search matches inside words (ross → 😵 face with crossed-out eyes). Skin tones,
  recently used, full 4-byte Unicode support.
• Images like on GitHub – relative paths resolve from the document’s folder, /path from the
  repository root. Drag & drop images and .md files into the window.
• Find & replace with match case, whole word and regular expressions ($1 groups).
• Safe – changes by other programs are detected (reload or ask, never overwritten silently),
  unsaved work is recovered after a crash, recently opened files in the Open menu.
• Open HTML – converted to Markdown; a dialog lists exactly what Markdown can’t keep.
• Export – standalone HTML file, HTML to the clipboard, print. Document zoom 50–300 %.
• Markdown shortcuts while typing (# , - , 1. , > , **bold**, [text](url) …).

Download

Get the installer Mark.O.Down_0.2.0_x64-setup.exe from the
latest release (Windows 10/11, 64-bit).
It needs Microsoft Edge WebView2, which is part of Windows 10/11 (the installer fetches it if missing).

„Windows protected your PC“? The installer is not code-signed yet. Click More info → Run anyway.

Drag & drop not working? Windows blocks drag & drop from Explorer into programs running
as administrator. Start Mark O Down normally – the status bar warns you if it runs elevated.

Keyboard shortcuts

Action	Keys
Open / Save / Save as	Ctrl+O / Ctrl+S / Ctrl+Shift+S
Close document / Print	Ctrl+W / Ctrl+P
Find / Find & replace / next / previous	Ctrl+F / Ctrl+H / F3 / Shift+F3
Zoom in / out / reset	Ctrl+Mouse wheel, Ctrl+Plus / Ctrl+Minus / Ctrl+0
Export HTML	Ctrl+Shift+E
Bold / Italic / Strikethrough / Code	Ctrl+B / Ctrl+I / Ctrl+Shift+X / Ctrl+E
Link	Ctrl+K
Emoji & symbols	Ctrl+.
Headings / Paragraph	Ctrl+Alt+1…3 / Ctrl+Alt+0
Bullet / numbered list / quote	Ctrl+Shift+8 / Ctrl+Shift+7 / Ctrl+Shift+9
Indent / outdent list item, next table cell	Tab / Shift+Tab
Line break	Shift+Enter
Show exported Markdown	Ctrl+Shift+M
Help	F1

Building from source

Requirements: Rust, Node.js 22+, and the
Tauri prerequisites for Windows.

npm install
npm run tauri dev      # run in development mode
npm run tauri build    # release build + installer in src-tauri/target/release/bundle/nsis/
npm test               # round-trip, editor and search tests
npm run unicode        # refresh the emoji/symbol data from unicode.org and CLDR

Releasing

Releases are built by GitHub Actions (release.yml) when a version tag is pushed:

npm run release:version 0.3.0   # sets the version in package.json, Cargo.toml, tauri.conf.json …
# add a "### 0.3.0 – <date>" section to the changelog in this README
git commit -am "Release v0.3.0"
git tag v0.3.0
git push origin main v0.3.0

The workflow checks that the tag matches the version, runs the tests, builds the installer and
creates a draft release with the setup attached. The release notes are taken from the matching
section of the changelog below – review the draft on GitHub and click Publish.
Tags with a suffix (v0.2.0-beta.1) become pre-releases. Every push and pull request runs the
test suite (ci.yml).

How it works

.md text ──micromark──▶ mdast (syntax tree) ──▶ ProseMirror document  (editing)
.md text ◀─to-markdown── mdast ◀──────────────── ProseMirror document  (saving)

• Parsing/serializing: remark (micromark, mdast, GFM) –
  100 % CommonMark compliant.
• Editor: ProseMirror with a schema that contains exactly the Markdown
  constructs, plus prosemirror-tables.
• Round-trip: every top-level block (and every item of a top-level list) remembers its original
  source and its canonical serialization at load time. On save, an unchanged block is written back
  from the original bytes; only edited blocks are re-serialized.
• Desktop shell: Tauri 2 (Rust) – file I/O with strict UTF-8, BOM and line
  ending handling, atomic saves, config and download cache.

The test suite round-trips its fixtures and all README files in node_modules byte-for-byte and
checks that full re-serialization renders identical HTML.

Changelog

0.2.0 – 2026-09-28

New

• Find & replace (Ctrl+F / Ctrl+H, F3 / Shift+F3): all matches highlighted with a
  counter, options match case, whole word (also for umlauts) and regular expression with
  $1 … in the replacement. Finds text inside formatting, lists, tables and code; Replace
  keeps the formatting, Replace all is a single undo step.
• Open HTML files (.html / .htm, also by drag & drop): converted to Markdown. Before
  importing, a dialog lists exactly what gets lost in this file (scripts, stylesheets, style /
  class attributes, <span>, <u> …). <div align="center">, <br> and <img> with size are
  kept, iframes become links. The result is a new document – the HTML file is never overwritten,
  Save proposes <name>.md next to it.
• Recently opened files: the Open button has a menu with the last 10 files; missing files are
  reported and removed from the list.
• Zoom 50–300 %: Ctrl+Mouse wheel (also touchpad pinch), Ctrl+Plus / Ctrl+Minus /
  Ctrl+0 and a − 100 % + control in the status bar. Only the document is scaled; the level is
  remembered.
• Search button in the toolbar.

Data safety

• Changes by other programs are detected (checked before every save and when the window gets
  focus): an unchanged document reloads silently, an edited one asks Reload / Keep mine.
  Saving never overwrites such changes without asking (Overwrite / Save as… / Cancel).
  A deleted file is reported; Save creates it again.
• Crash recovery: while there are unsaved changes, a copy is kept in the app data folder
  (never in the document itself). After a crash, power loss or forced restart, the next start offers
  to restore them.
• Text typed while a save is in progress is no longer marked as saved (closing the window would
  not have asked for it).
• Saving through a symbolic link updates the target and keeps the link.

Fixed

• Dialogs no longer let the keyboard focus escape: with a dialog open, Tab could move into the
  editor behind it and text went blindly into the document. All dialogs now share one frame with a
  locked background, consistent Esc, click-outside and focus return.
• Enter in the emoji and About dialogs acted even when another button (e.g. Cancel) was focused.
• The emoji grid was ~1,900 Tab stops; it is now one stop with arrow-key navigation.
• Images whose file names contain #, ? or % were not displayed.
• Downloading the icon list had no timeout and could hang forever when offline.
• At the default window width the toolbar wrapped into two rows.

Security

• Printing renders the document in a sandbox: scripts inside an untrusted .md file can’t run.

Performance

• Saving after an edit only serializes the changed blocks: 262 ms → 2 ms for a 1 MB document;
  list items no longer rebuild the whole list.

0.1.0 – 2026-09-28

First release.

• WYSIWYG editing of CommonMark + GitHub Flavored Markdown with lossless, byte-identical round-trip
  (BOM and CRLF/LF preserved, unchanged blocks written back from the original bytes).
• README-friendly HTML: <div align="center">, <br>, <img width> and <a><img></a>.
• Tables with toolbar (rows, columns, alignment), task lists, code blocks, raw HTML blocks.
• Badge & icon picker (shields.io, badgen.net, forthebadge.com, Simple Icons, own images) with
  configurable sources and offline cache.
• Emoji & symbol picker (Unicode 18, CLDR 48) with English and German search.
• Images like on GitHub (relative paths, /path from the repository root), drag & drop.
• HTML export, copy HTML, print, close document, Help and About.
• Windows installer (NSIS), .md file association.

License

MIT © 2026 Alexander Predl · Impressum