Terminal strobing/flickering after returning from session selection screen (Windows Terminal)

Environment

• Claude Code: 2.1.144
• Windows Terminal: 1.24.11321.0
• Shell: PowerShell 7.6.1
• OS: Windows 11 Pro 10.0.26200

Steps to Reproduce

1. Open Claude Code in Windows Terminal (PowerShell 7.6.1 profile in taskbar)
2. Navigate to the session selection screen
3. Click back into an active session where Claude is thinking (spinner visible)
4. Observe strobing/flickering in the terminal

What Happens

After re-entering the session:

• Terminal strobes/flickers while Claude is thinking (spinner animation)
• Strobing also occurs on every key press while typing a new prompt
• When Claude finishes thinking, the strobing stops
• When a new prompt is submitted and Claude starts thinking again, strobing resumes
• Issue persists for the entire duration of that terminal session
• Workaround: Closing and reopening the terminal window clears the bad state

Expected Behavior

Terminal renders cleanly after re-entering a session, with no flickering during the thinking animation or while typing.

Notes

The key-press strobing suggests the terminal gets into a corrupted render state when re-entering a session, not just a spinner animation issue. The problem appears to be in how Claude Code restores terminal state on session resume. Every subsequent render operation (cursor movement, input echo, spinner frame) triggers a full redraw instead of an in-place update.