[BUG] Claude desktop app hangs on startup on macOS 26.1

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?

Claude desktop app hangs on startup on macOS 26.1

macOS version: 26.1 (Darwin 25.1.0, Build 25B78)
Claude app version: 1.7196.1

On startup the app immediately shows a spinning beachball and never loads. Investigating the process list
shows the app is stuck waiting on:

diskutil image create blank --fs none --format ASIF --size 10GiB
.../vm_bundles/claudevm.bundle/sessiondata.img

The ASIF disk image format appears to not be supported on macOS 26 — running that command manually produces
no output and no file is created. The app hangs indefinitely waiting for the image.

Workaround: none; the web app works fine.

What Should Happen?

Claude should provide a fix

Error Messages/Logs

Steps to Reproduce

When opening the claude app it hands right away

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

laude Code CLI: 2.1.143

Platform

Other

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_