Quell Proxy Fixes Claude Code Scroll-Jumping on Windows

Quell is a small Rust proxy that fixes Claude Code's scroll-jumping issue on Windows. When Claude Code streams long responses, it uses synchronized output (DEC Mode 2026) and triggers full screen redraws that include clear-screen sequences, resetting your scroll position and causing the terminal to jump to the top.

How Quell Works

Quell sits between your terminal and Claude Code, detecting full-redraw sync blocks and stripping the clear-screen sequences before forwarding the output. Everything else passes through unchanged, keeping your scroll position stable.

Features

• Scroll position preservation - Prevents terminal from jumping to top during long Claude Code responses
• Shift+Enter for newlines - Instead of needing Alt+Enter (requires Windows Terminal 1.25+)
• Security filtering - Strips clipboard access attempts, dangerous URL schemes (ssh://, javascript://), and terminal query attacks from AI output
• Full Unicode support - Emoji, CJK characters, and box-drawing characters render correctly

Limitations

• Windows only - Uses Windows ConPTY, so macOS/Linux not supported yet
• Not a new terminal - Transparent proxy that wraps your existing terminal
• v0.1.0 - Early version with potential edge cases

Technical Details

Single executable with no configuration required. No network access or telemetry. MIT licensed. The tool was built with Claude Code itself.