💾 Nothing to save
It records as soon as you stop typing — no "Do you want to save changes?" when you close.
🗂️ Tabs and session restore
Quit, crash, or reboot — your open tabs come back, unsaved notes included. Tab bar with a + button, Ctrl+Tab cycling, right-click to close several at once.
📝 Live Markdown preview
Renders on the right as you type — GFM tables, checkboxes, highlighted code blocks, synced scrolling. Toggle with Ctrl/Cmd+Shift+M and drag the middle divider to set the split — the ratio and zoom are remembered per tab.
🔗 Follow document links
Click a [another doc](./other.md) link in the preview and that file opens in a new tab — with an #anchor on it, right at that spot. Every heading gets an anchor, so a document's own table of contents works, in the app and in the HTML you export. Web addresses still go to your browser; a missing file, a folder, or anything that isn't text is reported with the path it resolved to instead of being opened.
🪟 Open and close each pane
Turn the editor and the preview on or off per tab — full-width preview in this tab, editor only in that one. Hover the top-right corner of a pane for its × button; reopen from the Editor · Preview buttons in the status bar. The layout is remembered per tab too. Since .md and .mmd files are usually opened to be read, they start as preview only.
🧜 Mermaid diagrams
```mermaid code blocks, and whole .mmd files rendered as one picture — flowcharts, sequence, Gantt, class, anything Mermaid 11 draws. A wide diagram grows with the window, and you can zoom a chart on its own or pick its background color.
🖨️ Export the preview
Save the rendered document as a single HTML file, or print it straight to PDF — diagrams come along as images.
📋 Paste the web as Markdown
Copy a chatbot answer or a web page, paste it into a Markdown tab, and the headings, lists, tables and code blocks arrive as Markdown. Other file types paste verbatim, as before — turn it off under Preferences ▸ Editor ▸ Paste HTML as Markdown.
🎨 Syntax highlighting
143 languages, detected from the file name alone.
🌗 Ten themes, light or dark
Pick a palette — Dracula, GitHub, Solarized, Gruvbox, Catppuccin, Nord, Tokyo Night, One Half, Rosé Pine, Kanagawa — and its lightness separately under View ▸ Theme. System follows your OS appearance. The editor, the syntax colors, and the Markdown/Mermaid preview all switch together, and your choice sticks across restarts.
✂️ Line tools
Sort, remove duplicate or blank lines, trim whitespace, change case, move lines.
⌨️ Multiple cursors and code folding
Select every occurrence of a word and edit them at once; fold long blocks. Whitespace rendering included.
🌏 Legacy encodings
UTF-8 and UTF-16, plus EUC-KR/CP949, Shift-JIS, GBK, and Big5 — detected and opened correctly. Characters the chosen encoding can't represent are flagged before saving.
👀 External change detection
If another program edits the file while UniNotepad is running, it notices right away — refreshing quietly if you haven't typed anything, asking with a banner if you have.
🗄️ Large files, safely
Files over 10 MB open in a light mode (no syntax highlighting) after a confirmation, so the app never freezes.
⚙️ One place for settings
Font, line numbers, indentation, save options, and theme — all on one screen at Ctrl/Cmd+,.
🔄 Automatic update checks
New releases show up quietly in the status bar — Windows and AppImage builds install from inside the app.
🪶 Lightweight
It uses the OS web view instead of bundling a browser, so the installer is around 3 MB.
