[BUG] 2.1.211 on Windows Terminal: TUI renders duplicated/overlapping frames, cursor lands mid-line, pasted text mid-word (2.1.210 is clean)

Bug Description

After the auto-update to 2.1.211, TUI rendering breaks on Windows Terminal. The interface is drawn duplicated and overlapping: whole frames (assistant output, the input box, the "bypass permissions" status line) get painted twice, stacked on top of each other, and characters run together without spaces. The text cursor ends up in the middle of a line instead of at the input prompt, and pasted text is inserted between words rather than at the cursor position.

Ctrl+L redraws the screen cleanly for exactly one frame, but the corruption returns immediately on the next output/update, so it is not a usable workaround. It progressively gets worse with each additional assistant message.

Confirmed regression

Downgrading to 2.1.210 (claude install 2.1.210) fixes it completely: fresh, clean rendering across multiple back-and-forth messages. Verified on the same machine, same terminal, same resumed session: 2.1.210 = clean, 2.1.211 = broken. This started exactly when 2.1.211 landed (published 2026-07-15), which matches "it only started today" from the user side.

Steps to Reproduce

1. Run Claude Code 2.1.211 (native build) in Windows Terminal.
2. Have a normal back-and-forth conversation with several longer assistant messages.
3. Observe the TUI progressively rendering duplicated/overlapping lines; the input cursor drifts to mid-line; pasted text lands between words.
4. Ctrl+L fixes it for one frame only, then it corrupts again on the next render.

Expected

Single, clean render of the TUI, cursor at the input prompt, pasted text inserted at the cursor.

Actual

Duplicated/overlapping frames, cursor mid-line, paste mid-word. Only 2.1.211 is affected; 2.1.210 renders correctly.

What fixes it

claude install 2.1.210, plus disabling the auto-updater (DISABLE_AUTOUPDATER=1) so it does not silently jump back to 2.1.211.

Environment

• Claude Code: 2.1.211 (broken) vs 2.1.210 (clean), native build (~/.local/bin/claude.exe)
• OS: Windows 11 Pro, Build 26200
• Terminal: Windows Terminal 1.24.11321.0
• Shell: PowerShell

Related

Likely the same 2.1.211 rendering regression as #77969 ("Claude Code not displaying input prompts/text to user", reported the same day on 2.1.211). This report adds the Windows Terminal variant with the specific duplicated/overlapping-frame symptom and confirms 2.1.210 is clean, isolating it to 2.1.211.