MarkFold

Read .md files as documents. Diagrams (Mermaid, PlantUML), math, TOC, folder search, highlights & notes, HTML/PDF export.

Open a .md file in your browser and you get a properly rendered document instead of a wall of gray text. ■ ONE-TIME SETUP To open local .md files, go to chrome://extensions → MarkFold → Details and turn on "Allow access to file URLs". Chrome's security policy does not let an extension enable this for you. Markdown files served over the web work right away, with no setup. ■ DIAGRAMS - Mermaid: flowcharts, sequence, Gantt, class diagrams and more - PlantUML: configurable rendering server (point it at your own internal or local server) - Graphviz (DOT), Vega / Vega-Lite, nomnoml - Click a diagram to open a zoom lightbox; save as PNG (2x resolution) or SVG ■ LANGUAGE - Interface language: auto-detect from browser (default), English, or Korean. Switch instantly in settings - Falls back to English on unsupported browser languages ■ READING - Automatic table of contents that tracks your position as you scroll - Dark, light, or follow system setting - KaTeX math ($...$, $$...$$) - fonts are never loaded for documents without math - GitHub-style tables, footnotes, task lists, GFM alerts ([!NOTE] and friends), YAML front-matter cards - Syntax-highlighted code blocks with a copy button - Section-by-section lazy rendering, so very large documents stay responsive ■ FOLDER WORKSPACE (local files) - Tree of .md files in the same folder, full-text search, backlinks - Move between documents with [[wikilinks]] ■ ANNOTATIONS (highlights and notes) - Select text to highlight in 12 colors and attach a note - Your original .md file is never modified - everything is stored locally in the browser - Highlights reattach by surrounding text, so they survive edits to the document - Manage them in a list panel: jump to any highlight, or clear them all ■ EXPORT - Standalone HTML: images, fonts and styles all inlined into one file. Made to keep offline, indefinitely - PDF: optional cover page, table of contents, page size (A4/Letter) - Highlight shading and notes (as margin callouts) are included - one checkbox turns them off ■ EDITING - Split-screen editor (CodeMirror 6), live preview, two-way scroll sync - Ctrl+S writes straight back to the original file (only files you picked yourself) ■ PRESENTING - Hit ▶ Present for a fullscreen slideshow. Slides split on --- or on headings ■ PRIVACY Nothing is sent to our servers. There are no analytics, no tracking, and no accounts. One exception: PlantUML diagrams are drawn by an external rendering server, so the text of those code blocks is sent there (plantuml.com by default; switch to your own server in settings). Everything else is rendered inside your browser. Full policy: https://github.com/jhkook10/markfold-public/blob/main/PRIVACY.md