[BUG] React Hydration Error Prevents Claude Code Web Session Startup

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?

Issue Summary

Claude Code Web fails to start a new session due to a React hydration mismatch error (React Error #418). The error prevents the web interface from properly initializing and loading the coding environment.

Environment

• Platform: Claude Code on the Web
• Account Type: Max
• Browser: Google Chrome - Version 141.0.7390.122 (Official Build) (64-bit)
• Operating System: Ubuntu 24.04.3 LTS
• Date/Time: 2025-11-04

Steps to Reproduce

1. Navigate to Claude Code Web at claude.ai
2. Attempt to start a new coding session
3. Observe the error in browser console

What Should Happen?

Expected Behavior

Claude Code Web should successfully initialize and present the coding interface ready for use.

Actual Behavior

The web interface fails to load properly with a React hydration error. The session does not start successfully.

Error Messages/Logs

Error with Permissions-Policy header: Unrecognized feature: 'bluetooth'.
Error with Permissions-Policy header: Unrecognized feature: 'web-share'.
isolated-segment.html?v=tName%3E%20...:1 An iframe which has both allow-scripts and allow-same-origin for its sandbox attribute can escape its sandboxing.
5762-c11bceb7bceb728d.js:1 undefined
87c73c54-dd8d81ac9604067c.js:1 Uncaught Error: Minified React error #418; visit https://react.dev/errors/418?args[]=text&args[]= for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
    at rD (87c73c54-dd8d81ac9604067c.js:1:35060)
    at rO (87c73c54-dd8d81ac9604067c.js:1:36093)
    at 87c73c54-dd8d81ac9604067c.js:1:118081
    at ix (87c73c54-dd8d81ac9604067c.js:1:122953)
    at ik (87c73c54-dd8d81ac9604067c.js:1:114741)
    at 87c73c54-dd8d81ac9604067c.js:1:114525
    at ib (87c73c54-dd8d81ac9604067c.js:1:114533)
    at iu (87c73c54-dd8d81ac9604067c.js:1:110835)
    at iG (87c73c54-dd8d81ac9604067c.js:1:133053)
    at iW (87c73c54-dd8d81ac9604067c.js:1:131264)
global-error-6ecb4097c6c37554.js:1 [SERVICE_WORKER] Found 1 service worker(s), which are no longer used. Unregistering.
warn @ global-error-6ecb4097c6c37554.js:1
frame-modern.4da73d46.js:1 [Intercom] Launcher is disabled in settings or current page does not match display conditions

Steps to Reproduce

Steps to Reproduce

1. Navigate to Claude Code Web at claude.ai
2. Attempt to start a new coding session
3. Observe the error in browser console

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.0.32 (Claude Code)

Platform

Anthropic API

Operating System

Ubuntu/Debian Linux

Terminal/Shell

Other

Additional Information

_No response_