Rich Markdown Preview

Preview local Markdown files beautifully. Customizable themes, font selection, and auto-generated table of contents.

# Chrome Web Store Listing (English) ## Extension Name Rich Markdown Preview ## Short Description (132 characters max) The best way to read local Markdown. 25 themes, Japanese fonts, folder management, live sync, review comments & AI export. ## Detailed Description ### Read local Markdown files — beautifully, freely, your way. Preview Markdown written in VS Code, Vim, or any editor — right in your browser. With 25 themes, Japanese font support, full folder management, and live file sync, Rich Markdown Preview goes far beyond what other Markdown preview extensions offer. Built for those who care about how their documents look. --- ### Why Rich Markdown Preview? Most Markdown preview extensions just open a single file and display it. Rich Markdown Preview is different. - Open a folder and browse all your Markdown files in a tree view - Save in your editor, and the preview updates within 1 second — automatically - Work with multiple files using browser-like tabs - Reopen Chrome and your previous folders and tabs are restored instantly **Designed to be the preview pane that lives alongside your editor.** --- ### Key Features 📖 **Beautiful Markdown Rendering** - Full GitHub Flavored Markdown (GFM) support - Syntax highlighting for 170+ languages - Beautiful rendering of tables, lists, blockquotes, and images - Emoji shortcode support (:smile: → 😄) - Automatic frontmatter (YAML) removal - Secure HTML output via DOMPurify 🎨 **25 Preset Themes + Custom Themes** - Popular themes including GitHub Dark/Light, Dracula, Nord, Tokyo Night, Monokai, Catppuccin, Synthwave '84, and more - 10 light + 15 dark themes — switch instantly to match your mood or environment - Custom themes with 21 individually configurable color elements (almost no other extension lets you set H1–H6 heading colors separately) - Bulk color settings for accent, text, sub-background, and border colors - Create, save, manage, and delete custom themes 🔤 **Japanese-Optimized Font & Text Settings** - 5 Japanese fonts available with one click (Noto Sans JP / Noto Serif JP / Zen Kaku Gothic New / Zen Maru Gothic / M PLUS Rounded 1c) - Font size: adjustable from 12–32px - Line height: adjustable from 1–3× - Letter spacing: fine-tune from -0.05 to 0.2em - Content width in 4 levels (narrow / medium / wide / full) - Dynamic Google Fonts loading — cached after first use for fast rendering 📁 **Folder Management & Editor Sync** - Select a folder to display Markdown files in a tree view (up to 5 levels deep) - Supports .md / .markdown / .mdx / .mkd - Auto-detects file changes within 1 second and refreshes the preview - Toggle hidden files (dotfiles) on/off - Refresh button for instant directory updates - Right-click to copy file path or filename 📑 **Tab Management & Session Restore** - Manage multiple files with browser-like tabs - Drag and drop tabs to reorder freely - Drag and drop files from your desktop to open them instantly - Automatically restores previous folders and tabs on next launch (persisted via IndexedDB) 📑 **Auto-Generated Table of Contents** - Automatically builds TOC from H1–H6 headings - Click to smoothly scroll to any section - Real-time highlight of the current heading based on scroll position - TOC panel auto-scrolls to keep the active item visible - Toggle visibility with one click 🔍 **In-Document Search** - Ctrl+F / Cmd+F to open the search panel - Match count displayed as "X / Y" - Navigate between matches (Enter / Shift+Enter) - Highlighted matches with active match emphasis - Auto-scrolls to search results 📝 **Extended Markdown Support** - Mermaid diagrams (flowcharts, sequence diagrams, Gantt charts, and more) - Mermaid theme auto-switches between dark and light - Task lists (checkbox display) - Footnotes ([^1] syntax with auto-generated footnote section) - details / summary collapsible elements 💬 **Review Comments & AI Export** - Select text in the preview to add review comments - Two comment types: "Modify" and "Delete" - Unresolved / resolved status management for each comment - Highlighted comment anchors with click-to-scroll navigation - Export review comments as AI agent instructions (Markdown / JSON format) - Structured output organized by file and section - Clipboard copy & file download support - Comments persisted via IndexedDB and auto-restored on next launch 📋 **Copy Features** - Copy Markdown source with one click - Copy as rendered HTML (great for pasting into other apps) - Copy file path and filename ⌨️ **Keyboard Shortcuts** - Ctrl+F / Cmd+F: Open search - Escape: Close search - Enter: Next match - Shift+Enter: Previous match ⚙️ **Auto-Save Settings** - Theme, font, size, line height, letter spacing, content width, TOC visibility — all settings are saved automatically - Persisted via Chrome Storage API and restored instantly on next launch --- ### How It Compares | | Rich Markdown Preview | Typical Extensions | |---|---|---| | Directory tree view | ✅ Browse entire folders | ❌ Single file only | | Live file sync | ✅ Updates within 1 second | ❌ Manual reload | | Tab management | ✅ Multiple files at once | ❌ One file at a time | | Session restore | ✅ Folders & tabs auto-restored | ❌ Start from scratch | | Themes | ✅ 25 presets + unlimited custom | △ A few options | | Color customization | ✅ 21 elements individually | △ Background color only | | Japanese fonts | ✅ 5 typefaces | ❌ Rarely supported | | Mermaid diagrams | ✅ Auto theme switching | ❌ Rarely supported | | TOC + scroll sync | ✅ Real-time tracking | △ Static TOC | | Review comments | ✅ Select text to add + AI instruction export | ❌ Not supported | --- ### How to Use 1. Click the extension icon 2. Select "Open Folder" to choose a folder containing Markdown files 3. Select a file from the list to preview 4. Customize your theme and font settings to your liking 💡 You can also drag and drop files directly to open them. --- ### Privacy This extension: - Does not send any user data externally - Does not require internet connection (except for Google Fonts loading) - All data is stored locally - DOMPurify sanitizes Markdown to neutralize malicious scripts --- ## Category Productivity ## Languages Japanese, English