sbx save seems to run indefinitely on Mac

[jleser]

I'm on macOS Tahoe 26.4

The sbx save command below will run for at least 2.5 without completing at around 100% CPU. I must CTRL-C to stop it:

$ sbx save claude-apigw-services   myimage:v1.0
Sandbox claude-apigw-services started successfully
Stopping sandbox container ...
Snapshotting image in sandbox ...
^CERROR: failed to commit container: Post "http://%2Ftmp%2Fsboxd-502-sandboxes%2Fdocker.sock/v1.53/commit?author=Docker+Sandboxes&comment=Exported+from+sandbox&container=1f86807271f6de6332a1fd5ae6c6a666471a09d4a843e87b92221bfec3aeebc5&pause=0&repo=docker.io%2Flibrary%2Fmyimage&tag=v1.0": context canceled

Once I cancel, sbx is broken until I restart the system:

$ sbx list 
ERROR: failed to list runtimes: list runtimes: send request: Get "http://socket/runtime": net/http: request canceled (Client.Timeout exceeded while awaiting headers)

The sandbox in question was created using the default claude template:

$ sbx create claude .
INFO: Configuring Docker
✓ Created sandbox 'claude-apigw-services'
  Workspace: /Users/jleser/ws/apigw-services (direct mount)
  Agent: claude

To connect to this sandbox, run:
  sbx run claude-apigw-services

[robmry]

Hi @jleser - thank you for reporting this ... there's a bug in reading the sparse image file, a fix is in-progress.