v2.2.1

Packaging Fix

• Fixed the GitHub release packaging script to preserve required runtimes/ directories
• Fixed the GitHub release packaging script to preserve WinUI language resource folders such as en-us/ and zh-TW/
• Fixed blank-window and startup failures in the packaged zip build caused by missing Windows App SDK / WebView2 runtime resources

v2.2.0

• 2026-05-17

Optional AI Summary

• Added an optional AI Summary workflow with streaming inline output
• Added AI settings for endpoint, API key, model, and summary response language
• Added OpenAI-compatible endpoint normalization for Azure OpenAI and similar providers
• Added copy-to-clipboard support for generated summaries
• Added an AI Summary demo GIF and README notes for the validated AOAI + gpt-5.4-mini setup

UX and Safety

• Kept AI UI English-first while allowing summary output language override in the prompt
• Masked the API key field with peek-to-reveal behavior
• Kept the AI summary entry point hidden until AI is configured and usable

v2.1.0 — Offline Support & Code Quality

What's New in v2.1.0

🔌 Fully Offline — No Internet Required

• Mermaid.js (v11) and highlight.js (v11.9.0) are now bundled locally
• Assets served via WebView2 virtual host mapping — zero CDN dependency
• Syntax highlighting and diagram rendering work without any network access
• This is how a native desktop app should behave

🛠️ Modernized Codebase

• File-scoped namespaces (C# 10) across all source files
• Pattern matching: \is null\ / \is not null\ instead of == null\ / != null\
• Collection expressions, expression-bodied members, target-typed
  ew\
• Cleaner, more idiomatic C# throughout

📋 Housekeeping

• Updated THIRD-PARTY-NOTICES to reflect bundled (not CDN) assets
• Fixed version extraction in build script

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Thanks to the r/csharp community for the constructive feedback and code review suggestions — your input directly shaped this release. 🙏

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Download

Extract the zip anywhere and run \READU.md.exe. No installer needed.

Requirements: Windows 10 (1903+) or Windows 11 with WebView2 Runtime (pre-installed on most systems).

READU.md v2.0.0

What's New in v2.0.0

Major Features

• Multi-Tab — open multiple files simultaneously with drag-to-reorder tabs
• Edit Mode — side-by-side Markdown editor + live preview (Ctrl+E)
• Shell Rendering Architecture — CDN resources loaded once, instant tab switching
• Smart Mermaid Caching — SHA256-based incremental DOM updates preserve rendered diagrams
• Full Page Screenshot — capture entire rendered pages as PNG (Ctrl+Shift+S)
• Dark Mode — automatically follows your Windows system theme

Improvements

• Upgraded to .NET 9 + Windows App SDK 1.6
• Syntax highlighting via highlight.js (auto dark/light)
• Per-tab scroll position and zoom level preserved
• Hot reload when files change externally
• Deep blue gradient logo redesign

Download

• READU.md-v2.0.0-x64.zip — Portable x64 build (requires Windows 10 1903+)
• WebView2 Evergreen Runtime is required (pre-installed on Windows 10 20H2+ and all Windows 11)