[BUG] Prompt revision draft is lost once Arrow Up is pressed on Claude Extension for Visual Studio Code and Claude Code

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?

Sequence Arrow Up followed by Arrow Down does preserve drafts of reedited prompts, in some cases. Check provided steps.

Going deeper, this also affects v2.1.139 Claude Code

Very important! Altough this seems a duplicate of #6275, #37074 and #9492xxxx, this VERY ANNOYING behaviour that HAS NOT BEEN addressed yet.

What Should Happen?

Whenever navigation to previous prompts thru cursor up key occurs, current draft should never be lost, unless user explicitly allows/requests draft discard.

Error Messages/Logs

Steps to Reproduce

Open Claude Extension for Visual Studio Code

1. Start new chat
2. Type "_Prompt1_"
3. Press Enter key
4. Type "_Prompt2_"
5. Press Enter key
6. Press Arrow Up key. This recover "_Prompt2_" from history
7. Type "_Fixed_ ". This will adjust prompt to "_Fixed Prompt2_" and cursor will be at 7th position)
8. Press Arrow Up key. Tthis will move text cursor to 1th position)
9. Press Arrow Up key. This will recover "_Prompt1_" from history
10. Press Arrow Down key and you will get "_Prompt2_" instead of "_Fixed Prompt2_"

Claude Model

None

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.145

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

VS Code integrated terminal

Additional Information

_No response_