macOS ChatGPT Desktop 26.707.51957: new task creation silently fails and leaves an orphaned sidebar entry (no rollout found), while existing tasks and CLI work

Summary

After updating from the standalone Codex desktop app to the new ChatGPT desktop app (Powered by Codex & OWL), new Codex tasks can no longer be created successfully.

The issue started immediately after updating to ChatGPT Desktop 26.707.51957 on July 12, 2026.

Important correction: existing tasks work normally. The failure is specific to creating a new task:

• Submitting a prompt fails without any visible error or explanation.
• The UI still adds a sidebar entry named New task / 新任务, making it look as if a task was created.
• The underlying task/rollout does not actually exist. Opening the entry fails with no rollout found for thread id.

Codex CLI also works normally with the same account.

Environment

• Platform: macOS 15.7.7 (24G720)
• CPU architecture: Apple Silicon (arm64)
• App: ChatGPT Desktop (Powered by Codex & OWL)
• App version: 26.707.51957 (build 5175)
• App bundle identifier: com.openai.codex
• Codex CLI: codex-cli 0.144.1
• Plan: ChatGPT Pro

Regression

Everything worked normally before updating to the new ChatGPT desktop app.

Timeline:

• July 11: The standalone Codex desktop app could create new tasks normally.
• July 12: Updated to ChatGPT Desktop 26.707.51957.
• Immediately after the update, new-task creation began failing silently and leaving phantom sidebar entries that cannot be resumed.
• Existing tasks continue to work normally.

Steps to reproduce

Reproduced again at 2026-07-12 21:32:00 Asia/Shanghai:

1. Open ChatGPT Desktop 26.707.51957 and switch to Codex.
2. Open a repository. In this reproduction the repository was ux-data-knowledge on local branch main.
3. Start a new task and enter any prompt (for example, who are you).
4. Submit the prompt. It fails without displaying an error reason, and no response appears.
5. A new sidebar item named New task / 新任务 appears, making it look as though creation succeeded.
6. Click that new task entry.
7. The app displays:

Failed to resume task
no rollout found for thread id 019f551f-e6c7-7e13-beba-3024389f457e

The UI was localized in Chinese during this reproduction, where the banner read 未成功继续任务.

Actual behavior

New-task creation fails silently in the composer. The UI nevertheless creates a phantom/orphaned sidebar entry, but there is no corresponding usable task or rollout. Opening that entry then fails because no rollout exists for its thread ID.

Existing tasks remain usable.

Expected behavior

Submitting the first prompt should either create a real task with a persisted rollout, or display an explicit creation error. It must not add a sidebar entry for a task that does not actually exist.

Troubleshooting performed

• Signed out and back in.
• Fully quit and restarted the application.
• Tried multiple new tasks.
• Tested multiple repositories.

None changed the new-task failure. Existing tasks and Codex CLI continue to work.

Important observation

Both existing ChatGPT Desktop Codex tasks and Codex CLI work normally using the same OpenAI account. This suggests that account permissions, the ChatGPT Pro subscription, backend reachability, and repository access are valid.

The regression appears specific to the new ChatGPT Desktop application's new local task initialization and rollout persistence path. The sidebar entry appears to be created even though the underlying task initialization has failed.

Desktop log evidence

The desktop logs for the 21:32 reproduction show thread/start exceeding the desktop's 30-second timeout, followed by a successful response arriving about 10 seconds too late:

2026-07-12T13:31:09.498Z info ... conversationId=client-new-thread:875945a6-334c-48d5-a7cf-49d15a0bc139
2026-07-12T13:31:41.186Z warning ... method=thread/start ... timeoutMs=30000
2026-07-12T13:31:51.463Z info ... durationMs=40278 errorCode=null ... method=thread/start
2026-07-12T13:31:51.468Z error ... No promise for request ID ...
2026-07-12T13:32:11.233Z warning ... method=thread/start ... timeoutMs=30000
2026-07-12T13:32:11.243Z error ... Error creating local task errorMessage=Timeout
2026-07-12T13:32:11.244Z error ... [Composer] submit failed ... errorMessage=Timeout ... followUp=none mode=local
2026-07-12T13:32:21.884Z info ... durationMs=40656 errorCode=null ... method=thread/start
2026-07-12T13:32:21.886Z error ... No promise for request ID ...
2026-07-12T13:32:21.906Z info ... platform=darwin release=26.707.51957 sessionId=019f5686-c734-7922-b7c5-23752dc4e7c1

When the failed task entry shown in the UI is opened, thread/read succeeds but thread/resume immediately fails:

2026-07-12T13:33:47.199Z info ... conversationId=019f551f-e6c7-7e13-beba-3024389f457e ... errorCode=null ... method=thread/read
2026-07-12T13:33:47.287Z info ... conversationId=019f551f-e6c7-7e13-beba-3024389f457e ... errorCode=-32600 ... method=thread/resume
2026-07-12T13:33:47.288Z error ... message="no rollout found for thread id 019f551f-e6c7-7e13-beba-3024389f457e" ... method=thread/resume

The logs therefore suggest a timeout race in new-task initialization: thread/start completes after the renderer has discarded its pending request, leaving a sidebar-visible thread without a resumable rollout. This is an inference from the timestamps and request lifecycle above.

Full desktop logs are available on request. I have not attached the complete files because they contain local paths and account/session metadata.

Duplicate search / related historical reports

Before filing, I searched openai/codex Issues created since July 10, 2026. No issue contained the exact no rollout found error, and I found no report matching the 26.707.51957 Codex App to ChatGPT Desktop migration regression.

There are older reports with similar symptoms, including #11727 and #14396, but they concern earlier VS Code/Codex Desktop versions and different triggering conditions.

Because existing tasks and CLI work while every newly initialized desktop task fails after the July 12 migration, this appears to be a new regression in the desktop new-task path.

If additional diagnostics or sanitized logs are needed, I am happy to provide them.