/clear may blank the entire screen and hide subsequent input in long sessions with NO_FLICKER enabled

Summary

When NO_FLICKER is enabled, running /clear in a long Claude Code session can sometimes blank the entire terminal UI unexpectedly. This clears not only the conversation area, but also the banner/header. After that, newly typed commands may become invisible as well.

The session does not appear to be fully dead — after some time, the UI may recover and rendering resumes. This looks like a terminal redraw/rendering issue related to /clear under NO_FLICKER, especially in long sessions.

Environment

• Claude Code version: 2.1.98
• OS: macOS 15.6.0 (Darwin 24.6.0)
• Shell: zsh
• Terminal: Apple Terminal
• TERM: xterm-256color
• NO_FLICKER: enabled
• tmux/screen: no
• Session length: long-running session / large conversation history

Steps to reproduce

1. Start Claude Code with NO_FLICKER enabled
2. Use the same session for a while until the conversation becomes long
3. Run /clear
4. Immediately type another command

Expected behavior

• /clear should clear only the intended visible conversation area
• The banner/header should not disappear unexpectedly
• Newly typed commands should remain visible immediately
• The UI should remain stable after /clear

Actual behavior

• The entire screen is cleared, including the banner/header
• Newly typed commands are not visible
• The session still seems alive, but terminal rendering appears broken
• After some time, the UI may recover on its own

Reproducibility

Not obviously 100% reproducible, but it seems more likely in longer sessions and under NO_FLICKER.

Impact

This makes Claude Code look frozen or broken even though the session may still be active. It becomes difficult to tell whether input was received, which interrupts normal usage.

Notes / Hypothesis

This may be related to screen redraw handling after /clear when NO_FLICKER is active, especially with a larger in-memory/rendered session state.