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Preview of Markdown Viewer Pro

Markdown Viewer Pro by Soul in Silicon

The cleanest way to read Markdown in Firefox — open any .md file locally or on the web and get a beautifully rendered, fully interactive document instantly.

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About this extension
✨ Why Markdown Viewer Pro?

Most browsers show Markdown files as raw, unformatted text. Markdown Viewer Pro transforms them into polished, readable documents — with zero configuration required. Whether you're reviewing a project README, reading documentation, or writing notes, your files look exactly as intended.



🚀 Key Features

Beautiful Rendering
  • GitHub-Flavored Markdown — headings, bold/italic, tables, task lists, strikethrough, blockquotes, and more rendered flawlessly
  • Syntax-highlighted code blocks — 180+ languages powered by highlight.js with GitHub's signature colour themes
  • Smart typography — curly quotes, em-dashes, and ellipses automatically applied

Dark & Light Themes
  • Toggle between light and dark mode with a single click — or press D
  • GitHub-accurate colour palettes for both themes, including syntax highlighting
  • Your preference is remembered across sessions

Navigation & Reading
  • Auto-generated Table of Contents — jump to any section instantly, toggle with T
  • Reading progress bar — always know how far through a document you are
  • Heading anchor links — hover any heading to copy a direct link
  • Smooth scroll to sections from the TOC

Developer Friendly
  • Copy the raw Markdown source in one click
  • Per-block code copy button on every code block (appears on hover)
  • External links automatically open in a new tab
  • Works on local files (file://) and web-hosted .md URLs

Fully Customisable
  • Font size controls — A− and A+ buttons to find your perfect reading size
  • Line width — choose narrow, normal, wide, or full-width layouts
  • Settings panel — all preferences accessible from the toolbar icon
  • Everything persisted via browser storage — your setup survives restarts

Print Ready
  • Toolbar, TOC, and buttons are automatically hidden when printing
  • Link URLs are expanded inline so printed copies remain useful



🔒 Privacy & Security
  • Zero data collection — no analytics, no telemetry, no network requests
  • All rendering happens 100% locally in your browser
  • Dangerous URLs (javascript:, data:) in Markdown are automatically blocked
  • Minimal permissions: only what is strictly necessary to render files

Permissions requested:

| Permission | Why |
|---|---|
| file:///* | Read local .md files you open |
| storage | Save your display preferences |
| activeTab | Show file status in the popup |
| clipboardWrite | Copy source / copy code buttons |



⌨️ Keyboard Shortcuts

| Key | Action |
|-----|--------|
| T | Toggle Table of Contents |
| D | Toggle Dark / Light mode |



📂 Supported File Extensions

.md · .markdown · .mdown · .mkd · .mkdn
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Permissions and data

Required permissions:

  • Input data to the clipboard
  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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Version
1.0.0
Size
83.13 KB
Last updated
2 months ago (Apr 2, 2026)
Related Categories
  • Other
License
MIT License
Version History
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