I kept needing a quick way to check Markdown (especially Mermaid diagrams and GitHub-style alerts) without pasting into some random online editor that uploads my content to a server. So I built Markdown Preview: a fast, client-side Markdown editor/previewer that never sends your docs anywhere. Privacy was a hard requirement for me: everything runs in the browser. You can open sensitive drafts and nothing hits a backend that could log or store them. What it does: Fully local: no server-side processing of your Markdown Local AI text editing (Chrome on-device Write / Rewrite / Proofread when available) Local text-to-speech with word highlighting (read aloud in supported browsers) Live split-pane editor + HTML preview Mermaid diagrams, GitHub alerts, emoji shortcodes, syntax highlighting Shareable links (Markdown compressed into the URL hash; still all client-side) Present / Slides modes for walking a doc by headings Paste images in as base64 Markdown images Installable PWA (works offline; can open .md files via “Open with” on Chromium desktop) Try it: https://dev.ericperret.org/markdown/ Source: https://github.com/humaknlght/markdownweb Stack is mostly vanilla JS with marked, DOMPurify, highlight.js, and Mermaid loaded on demand. I spent a surprising amount of time on share-link compression, CSP/SRI for CDN deps, and treating shared/uploaded Markdown as untrusted until you Accept it. What’s next / still rough: mobile layout could use polish, share links can get truncated by some apps for very long docs, and the on-device AI tools only show up in Chrome builds that expose those APIs. Curious what would make you actually install something like this over other similar apps: stronger privacy messaging, better mobile UX, personal cloud storage, or something else?   submitted by   /u/humaknlght [link]   [comments]