Chinese IME corruption when editing directly pasted formatted assistant output in ChatGPT web and Windows app

What version of the Codex App are you using (From “About Codex” dialog)?

ChatGPT 26.715.21425 (Windows desktop app, powered by Codex & OWL)

What subscription do you have?

ChatGPT Plus

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x64

What issue are you seeing?

When formatted content copied directly from a ChatGPT assistant response is pasted into the ChatGPT composer, editing the pasted text with Microsoft Pinyin may corrupt Chinese input.

The issue occurs when inserting Chinese text immediately after punctuation in the pasted content. Existing punctuation may disappear, the committed Chinese character may be inserted in the wrong position, or a Pinyin composition letter may remain.

The issue can be reproduced in both ChatGPT web and the Windows desktop app. It does not occur when the same content is typed manually or passed through Windows Notepad before being pasted.

What steps can reproduce the bug?

Feedback ID: no-active-thread-019f6f65-f03c-7e33-bebe-68c9c4f1152f

1. Ask ChatGPT to generate formatted multiline text containing punctuation and a numbered list, for example:

标题：示例内容

事项：
1. 第一项
2. 第二项
3. 第三项

1. Copy the formatted text directly from the assistant response.

1. Paste it directly into the ChatGPT message composer.

1. Move the cursor immediately after punctuation in the pasted content, for example: 标题：|

The | symbol represents the cursor position.

1. Use Microsoft Pinyin to type a Chinese character and confirm the candidate using either the Space key or a number key.

1. Observe that the punctuation or surrounding text may be corrupted. For example, editing after 1. may produce text similar to 1我w.

What is the expected behavior?

Chinese text should be inserted exactly at the cursor position.

Existing punctuation and surrounding text should remain unchanged, characters should not be reordered, and no Pinyin composition letters should remain after the candidate is confirmed.

Additional information

Control tests:

• Manually typing the same content does not reproduce the issue.
• English input works normally.
• Microsoft Pinyin works normally in other applications.
• Pasting the content into Windows Notepad first, copying it again, and then pasting it into ChatGPT prevents the issue.

The Notepad workaround suggests that the issue may be triggered by rich-text or HTML clipboard data rather than the plain-text content itself.

Environment:

• OS: Windows 11
• Windows app version: ChatGPT 26.715.21425
• Input method: Microsoft Pinyin
• Input language: Chinese