[BUG] v1.8555 Breaks Cowork Causing 403 Expired Token on Authentication

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?

Upgraded Claude app on MacOS from v1.6259.1 to v1.8555.0 and tried to use Cowork but it never responded and kept showing the following error message. It used to work on v1.6259.1

<img width="605" height="352" alt="Image" src="https://github.com/user-attachments/assets/182b7ca8-58e3-4483-abd9-0b919d04ffa0" />

<img width="271" height="96" alt="Image" src="https://github.com/user-attachments/assets/112cad9a-0ab6-4478-868c-d2297b8140b5" />

What Should Happen?

should work normally without authentication errors

Error Messages/Logs

Failed to authenticate. API Error: 403 The security token included in the request is expired

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Failed to authenticate. API Error: 403 The security token included in the request is expired
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Steps to Reproduce

Update to v1.8555.0
Try to use Cowork

Claude Model

Not sure / Multiple models

Is this a regression?

Yes, this worked in a previous version

Last Working Version

v1.6259.1

Claude Code Version

v1.8555.0

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Other

Additional Information

Tried restarting the app
tried logging out
then it worked finally when I reused the older dmg file to revert to v1.6