A secure, extensible Markdown preview extension for VS Code, with an interactive Mermaid and image experience.
Features
Live preview — open the preview in a side editor and it refreshes as you type (configurable delay).
Editor title icon — a preview button appears in the top-right of the editor for Markdown files.
Mermaid diagrams — full rendering with zoom, pan, reset, and fullscreen controls.
Zoomable images — every image (including SVG) can be zoomed, panned, reset, and viewed fullscreen via Ctrl/Cmd + wheel or the toolbar.
Bidirectional scroll sync — the preview follows the active editor's visible range (and optionally the reverse).
Floating table of contents — a collapsible outline panel that highlights the current section.
Scroll position restore — the preview remembers where you were across refreshes.
Safe by default — strict Webview CSP, HTML sanitization (DOMPurify), and restricted local resource access.
Commands
Command
Description
Enhanced Markdown Preview: Open Preview
Open the preview in the side editor
Enhanced Markdown Preview: Open Preview to Side
Open the preview to the side
Enhanced Markdown Preview: Refresh Preview
Force-refresh the preview
Configuration
Setting
Default
Description
enhancedMarkdownPreview.updateDelay
200
Delay (ms) before refreshing the preview after an edit.
enhancedMarkdownPreview.openRemoteImages
false
Allow HTTPS images in the preview.
enhancedMarkdownPreview.scrollSync
true
Scroll the preview to follow the active editor's visible range.
enhancedMarkdownPreview.previewScrollSync
false
Scroll the editor to follow the preview when the preview is scrolled.
Development
npm install
npm run check # type check
npm run build # bundle extension + webview + css
npm run test:unit # unit + webview (jsdom) tests
npm run test:integration # Electron integration tests (downloads VS Code on first run)
npm test runs the full pipeline: check, build, unit tests, and integration tests.
Building the extension
npm run package
This produces a .vsix file in the project root that can be installed via Extensions: Install from VSIX….
