Markdown Hero

Markdown Hero — Safe Markdown Writing for Gmail

Markdown Hero brings clean, distraction-free Markdown authoring directly into Gmail — with a live preview, safe insertion, and local-only processing.

Write emails in Markdown, preview exactly how they’ll render, and insert formatted HTML into Gmail without ever sending your content anywhere.

Write Emails in Markdown — Safely

Markdown Hero adds a movable, resizable Markdown editor overlay to Gmail compose windows.

You can draft in Markdown while seeing a live rendered preview beside your text — similar to notebook or documentation tools — then insert the formatted result into your email with one click.

Your original message is never replaced without confirmation, and automatic snapshots protect against accidental loss.

Privacy-First by Design

Markdown Hero operates entirely inside your browser.

No servers

No tracking

No external requests

No content collection

No AI processing

Your email content never leaves your device.

Loss-Protection & Safe Editing

Markdown Hero is built to avoid accidental overwrites:

Automatic compose snapshots

Restore previous content anytime

Unsaved-changes indicator

Confirm-before-close protection

Insert only on explicit user action

You always stay in control of what goes into Gmail.

Live Preview — Notebook Style

As you type Markdown, the preview updates instantly:

Headings

Lists

Quotes

Inline code

Code blocks

Links

Emphasis

Scroll position stays synced between editor and preview for a smooth drafting experience.

Newline Mode Toggle

Different writers expect different behavior when pressing Enter/Return. Markdown Hero supports both styles:

Compose mode Single Enter = visible line break (email-style)

Markdown mode Blank line = new paragraph (standard Markdown)

Switch instantly with the Markdown ⇄ Compose slider.

Seamless Gmail Integration

Markdown Hero detects Gmail compose windows automatically and binds safely to the active editor.

The overlay is:

Movable

Resizable

Non-blocking (Gmail remains clickable)

Context-aware

Keyboard-friendly

ESC closes the panel (with confirmation if needed). Ctrl/Cmd+Enter inserts formatted content.

Local Markdown Engine

Markdown is parsed locally using a bundled parser and sanitized before insertion to ensure Gmail-safe HTML output.

No external libraries are loaded at runtime.

Who It’s For

Markdown Hero is designed for people who write structured emails:

Developers

Technical professionals

Documentation writers

Researchers

Markdown users

Power Gmail users

If you already think in Markdown, this makes Gmail feel native.

What Markdown Hero Does NOT Do

To keep the extension safe and predictable:

No AI rewriting

No cloud sync

No analytics

No permissions beyond Gmail

No modification without user action

It is a focused Markdown drafting tool — nothing more.

Permissions

Markdown Hero only runs on:

mail.google.com

This is required to detect Gmail compose windows and insert formatted content.

Markdown Hero turns Gmail into a safe Markdown writing environment with live preview, loss protection, and local-only processing.

Write clearly. Preview instantly. Insert safely.