Developer launches free browser-based Markdown editor with math, diagrams, and slides

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A developer has released Markdown Preview, a free, fully browser-based Markdown editor that requires no account or backend setup. The tool supports GitHub Flavored Markdown, KaTeX math rendering, Mermaid diagrams, syntax highlighting for over 180 languages, and a presentation slide mode. All documents are stored locally in the browser via IndexedDB and localStorage, and the app can be installed as a PWA for offline use. Users can copy formatted content directly into Gmail, Google Docs, or Slack without losing styling, and can open files from GitHub, GitLab, or Bitbucket via URL. The editor also offers PDF and HTML export, a command palette, find-and-replace, and automatic version snapshots, with no paid tiers or watermarks.

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