Vietnamese text input renders with corrupted/doubled diacritical marks

Summary

When typing Vietnamese text in the terminal input on Windows, characters with compound Unicode diacritics (tone mark + vowel modifier) are rendered incorrectly. The base vowel, modifier, and tone mark appear as separate visible characters instead of a single composed glyph.

Expected Behavior

Vietnamese characters with compound diacritics render as single composed glyphs. For example:

• gặp displays as gặp
• lỗi displays as lỗi
• những displays as những

Actual Behavior

Characters with compound diacritics are split/doubled when typed. Examples of what appears on screen:

• gặp → rendered as gaạpaập
• lỗi → rendered as lôiỗi
• những → rendered as nhunữững
• cập nhật → rendered as câạp nhâật

Screenshot showing the bug:

Steps to reproduce the issue

1. Open command-code v0.27.0 in VS Code terminal on Windows 11
2. Switch input language to Vietnamese (Telex or VNI input method)
3. Type any Vietnamese sentence with compound diacritics, e.g.: gặp lỗi trong những bản cập nhật
4. Observe the rendered text in the input field

Command Code Version

v0.27.0

Operating System

Windows

Terminal/IDE

VSCode

Shell

PowerShell

Additional context

No response

レポートでは、ソースファイルもテストも特定されていません。まず、Windows 11 上の VS Code ターミナルで、PowerShell とベトナム語の Telex または VNI 入力を使用して問題を再現し、その後、ターミナル入力のレンダリングパスを追跡してください。完了条件は、一覧にある例について、ベトナム語の複合ダイアクリティカルマークが単一の合成グリフとして表示されることです。