Markdown Hero

Local-only Markdown sandbox + live preview + safe insert for Gmail.

**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.