[BUG] claude code CLI - Terminal screen goes blank when typing after restoring VS Code panel from maximized state

[komealy]

Preflight Checklist

• I have searched existing issues and this hasn't been reported yet
• This is a single bug report (please file separate reports for different bugs)
• I am using the latest version of Claude Code

What's Wrong?

Environment

• OS: macOS (Darwin 25.3.0)
• IDE: VS Code version: 1.109.4
• Claude Code version: 2.1.45

Expected behavior

Typing should continue to render normally after restoring the panel from maximized state.

Actual behavior

The terminal screen goes blank on the first space character typed after restoring. Ctrl+C forces a re-render and recovers.

Notes

• The space character appears to be the specific trigger — typing non-space characters before the first space does not cause the blank.
• This is reproducible every time with the above steps.
• Likely a terminal resize/reflow issue: the TUI renderer may be holding stale dimensions from the maximized state, and the input component recalculates layout at word boundaries (spaces), causing escape sequences that clear or overflow the visible viewport at the smaller restored size.

What Should Happen?

No screen blanking.
No interruption of input.

Error Messages/Logs

Steps to Reproduce

1. Open Claude Code in the VS Code integrated terminal.
2. Click the internal terminal maximize button to fill the VS Code window with the terminal panel.
3. Submit at least one chat message while the terminal panel is maximized.
4. Restore the panel back to its original (non-maximized) size.
5. Begin typing a new message. As soon as you type a space character, the terminal screen goes completely blank.
6. Pressing Ctrl+C resets the terminal and the input becomes visible again.

Claude Model

Not sure / Multiple models

Is this a regression?

No, this never worked

Last Working Version

No response

Claude Code Version

2.1.45

Platform

AWS Bedrock

Operating System

macOS

Terminal/Shell

VS Code integrated terminal

Additional Information

No response

[komealy]

This is NOT a duplicate issue.

Claude Desktop vs. Claude Code CLI differentiation here.

There is #26080 for Claude Desktop.

This issue is to track the fix for Claude Code CLI that will be rendering in someone else's electron possibly. VSCode is only one example, and any other VSCode-ish IDE would be included here.

When running outside of electron, like in alacritty, I cannot reproduce the issue. It seems to be something that electron is messing with.

[komealy]

Source analysis of cli.js v2.1.45 — what we ruled out:

• Vanilla Ink 6.7.0 with the same layout (full-height, bottom-aligned messages) redraws correctly after maximize→restore. Not a vanilla Ink bug.
• Raw ANSI with the same escape sequences (clearTerminal = ESC[2J + ESC[3J + ESC[H, synchronized updates via DEC 2026, double-buffered viewport comparison) also handles resize correctly.

The bug is in the custom screen renderer (frontFrame/backFrame cell-level diffing, Dq8 diff builder, y05 full-screen render) — the layer between Ink and terminal output.

[komealy]

Still an issue, and easily reproducable in claude code 2.1.49.

[komealy]

Update (v2.1.52):

I think I can see what's happening now. When restoring the VS Code panel from maximized state, a large number of blank lines are being injected in the footer area (possibly from the status line rendering). This pushes the conversation content so far off screen that the terminal appears completely blank.

Starting with a taller bottom panel made the mechanism visible — you can see the content partially displaced with blank space below it, rather than fully scrolled out of view.

Additionally: the number of blank lines injected appears proportional to the height of the editor area above the terminal panel. If the editor shows ~5 lines, ~5 blank lines appear in the footer. If the editor shows many lines, many blank lines appear. This suggests the resize calculation may be using the wrong height reference (possibly total terminal height or editor height instead of just the panel height).

[komealy]

Still reproducible in v2.1.56. Additionally, this is not limited to maximize/restore — manually resizing the terminal panel (dragging the divider) also triggers the blank line injection.

[komealy]

Root Cause Found: terminal.integrated.stickyScroll.enabled

Disabling sticky scroll in VS Code terminal settings eliminates the bug entirely.

"terminal.integrated.stickyScroll.enabled": false

Testing methodology

1. Started with sticky scroll on (default) — bug reproduces consistently
2. Turned sticky scroll off, started a new Claude Code session — bug does not reproduce
3. Turned sticky scroll back on, started a new session — bug reproduces again

Notes

• The setting change requires a new terminal session to take effect. Toggling mid-session gave a false negative initially.
• This is likely a VS Code terminal stickyScroll interaction with panel resize — the sticky scroll component probably holds stale dimensions from the maximized/larger state, causing the reflow/blank on the first space character.
• still reproducible in version 2.1.62

[github-actions]

Closing for now — inactive for too long. Please open a new issue if this is still relevant.

[github-actions]

This issue has been automatically locked since it was closed and has not had any activity for 7 days. If you're experiencing a similar issue, please file a new issue and reference this one if it's relevant.