[BUG] Thai vowel "sara aa" (สระอา) not captured in input on Windows

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?

Description:

• Windows 11/10, Thai locale
• Claude Code version: [2.1.23]
• Thai vowel สระอา (U+0E32) disappears when typing
• Copy/paste also doesn't work
• Previously worked fine, started after recent update
• Output displays Thai correctly, only input is affected

What Should Happen?

Thai vowel "sara aa" (สระอา, U+0E32) should be captured and displayed correctly when typing or pasting in the Claude Code input prompt, just like it worked in previous versions.

Expected behavior:

• Typing "สระอา" should display "สระอา" (with the vowel visible)
• Copy/paste of Thai text containing สระอา should preserve the character
• All Thai characters including combining vowels should work correctly in input

This worked correctly before and stopped working after a recent update.

Error Messages/Logs

Steps to Reproduce

1. Open Claude Code (version 1.0.23) on Windows 11 with Thai locale
2. Switch keyboard input to Thai language
3. Type any word containing Thai vowel "sara aa" (สระอา), for example: "ภาษา" or "อา"
4. Observe that the "sara aa" character (U+0E32) does not appear in the input
5. Try copy/paste Thai text containing สระอา from another application - same issue, the character is missing
6. Note: Output from Claude displays Thai correctly, only input is affected

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.23

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

1. Open Claude Code on Windows with Thai locale
2. Switch keyboard to Thai language
3. Type any word containing สระอา (sara aa), e.g., "ภาษา" or "สระอา"
4. Observe that the สระอา character does not appear
5. Try copy/paste Thai text containing สระอา - same issue