[macOS] Computer Use and BUZZ ACP continue after Codex is closed

Summary

On macOS, after the user closed/stopped the Codex UI/task, Computer Use did not fully stop. The Computer Use cursor remained visible and the external BUZZ desktop app continued to receive or attempt input, including an attempt to change BUZZ settings without an active Codex task.

This is a user-control and safety issue: closing or stopping Codex must guarantee that no agent or Computer Use process can continue acting in another app.

Environment

• Codex desktop: 26.727.51351 (build 6119)
• macOS: 26.5.2 (25F84)
• BUZZ: 0.5.4
• Observed: 2026-08-05, JST

What we observed

1. The user closed/stopped Codex after a Computer Use/BUZZ interaction.
2. The Computer Use cursor remained visible.
3. A detached cua_node ... kernel.js process remained with PPID 1 and a BUZZ working directory.
4. BUZZ buzz-acp and Codex ACP processes remained and/or restarted. The user observed them attempting to change BUZZ settings.
5. Sending TERM to the detached Computer Use kernel alone was insufficient: BUZZ regenerated ACP children.
6. Stopping the BUZZ parent and the Computer Use service was required. A follow-up process check then found no BUZZ, ACP, or Computer Use kernel processes.

Expected behavior

• Closing or cancelling Codex synchronously cancels all active agent and Computer Use sessions.
• All child kernels, ACP bridges, helpers, and cursor overlays terminate.
• No further mouse or keyboard input is delivered to any external app after Codex exits.
• The UI exposes a reliable stop/kill state.

Actual behavior

• The cursor and Computer Use state outlived the user's Codex stop/close action.
• Agent/ACP processes were orphaned and could continue or restart.
• An external app could receive unwanted configuration-changing input after the user believed Codex had stopped.

Impact

Potential unauthorized changes to external application settings and loss of user control.

Request

Please investigate macOS process/session lifecycle and shutdown cleanup for Computer Use and ACP bridges. Shutdown should invalidate the session, terminate descendants, release cursor overlays, and prevent external input after the Codex task or app is stopped.

No personal paths, credentials, or BUZZ settings contents are included in this report.