### Preflight Checklist - [x] I have searched [existing issues](https://github.com/anthropics/claude-code/issues?q=is%3Aissue%20state%3Aopen%20label%3Abug) and this hasn't been reported yet - [x] This is a single bug report (please file separate reports for different bugs) - [x] I am using the latest version of Claude Code ### What's Wrong? When typing input into Claude Code, shift+letter is rendered as lowercase instead of uppercase. The problem only appeared today, likely with a fresh updat

[BUG] v2.1.83 broke uppercase letters in xterm under Linux

Status Fixed / completed

Reported on v2.1.83

Maintainer reply ✓ Yes — claude[bot]

Activity 7 comments · opened Mar 25, 2026 · closed Apr 17, 2026

💡 Likely answer: A maintainer (claude[bot], contributor) responded on this thread — see the highlighted reply below.

Preflight Checklist

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

What's Wrong?

When typing input into Claude Code, shift+letter is rendered as lowercase instead of uppercase. The problem only appeared today, likely with a fresh update of Claude Code.

What Should Happen?

Of course uppercase should again be rendered as uppercase.

Error Messages/Logs

Steps to Reproduce

Run Claude Code, get to the first prompt, enter 'x', get 'X'.

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.83 (Claude Code)

Platform

Anthropic API

Operating System

Ubuntu/Debian Linux

Terminal/Shell

Xterm

Additional Information

_No response_

View original on GitHub ↗

7 Comments

github-actions[bot] · 5 months ago

Found 3 possible duplicate issues:

This issue will be automatically closed as a duplicate in 3 days.

If your issue is a duplicate, please close it and 👍 the existing issue instead
To prevent auto-closure, add a comment or 👎 this comment

🤖 Generated with Claude Code

jwuttke · 5 months ago

Perhaps the root cause of all these issues is the same. Yet none of the other issues described misbehavior under Linux and XTerm. Therefore not a duplicate.

mbrand1 · 5 months ago

I noticed this today as well. Only thing I can add is I can turn on CAPS LOCK and then I get uppercase characters in the CLI (obviously this isn't practical). But the SHIFT no longer outputs an uppercase char. Running 2.1.83 inside xterm.

$ xterm -version
XTerm(379)

I downgraded to 2.1.81 and I have uppercase back:

curl -fsSL https://claude.ai/install.sh | bash -s 2.1.81

Moult · 5 months ago

Also just noticed this today. Linux + Xterm too.

davidkrauser · 4 months ago

Upgraded to 2.1.92, and this is now fixed for me.

claude[bot] contributor · 4 months ago

This issue was fixed as of version 2.1.98.

github-actions[bot] · 4 months ago

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.