[BUG] Error 300

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?

I've gotten this issue multiple times across a few chat windows with Claude Code in VSCode. It causes data loss. I search Error 300 and "Error 300". The former gave plenty of results, but the latter gave none. Claude Code recommended I report here.

What Should Happen?

Claude should not stop abruptly causing data loss in the immediate window.

Error Messages/Logs

Failed to render content: Minified React error #300; visit https://reactjs.org/docs/error-decoder.html?invariant=300 for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
[Troubleshooting resources](https://code.claude.com/docs/en/vs-code#troubleshooting)

Steps to Reproduce

Can't reproduce, it just happens because Claude.

Claude Model

Not sure / Multiple models

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

I'm powered by Claude Opus 4.5 (model ID: claude-opus-4-5-20251101). I'm running inside the Claude Code VSCode extension, but I don't have visibility into the extension's version number itself - that would be shown in your VSCode extensions panel or by running claude --version in your terminal.

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_