[Windows Desktop] Active Codex chats unexpectedly disappear without a delete action

What version of the Codex App are you using?

Desktop/bundled component version visible in the local installation: 26.818.61809. The About dialog was not available while preparing this report.

What platform is your computer?

Windows x64, working in a local WSL project workspace.

What issue are you seeing?

An active Codex chat unexpectedly disappears during normal work even though the user did not delete or archive it. This has happened more than once.

In the latest occurrence, the task had a long multi-turn conversation and had performed local code/configuration work across several repositories. The visible chat disappeared, making it look as though the conversation had been deleted and its context lost.

A read-only check immediately afterward showed that the underlying Codex task still existed in the desktop task inventory, was marked active, and had a recent updatedAt value. The agent was also able to continue from the retained task context after the user sent another message.

This suggests a desktop renderer/sidebar/conversation-index reconciliation problem rather than a confirmed deletion of the underlying task data. However, from the user's perspective the chat is deleted and the work history is lost.

No delete, archive, reset, cleanup, or task-management action was requested or executed before the disappearance.

What steps can reproduce the bug?

The exact trigger is not yet isolated, but both observed occurrences followed this pattern:

1. Open a Codex Desktop task on Windows.
2. Continue a substantial multi-turn task with local tool calls and code changes.
3. Do not delete or archive the task.
4. During continued use, observe that the active chat/history disappears from the UI.
5. Send a new message or inspect the task inventory.
6. The underlying task may still be returned as active even though its chat was no longer visible normally.

The problem is intermittent but recurring.

What is the expected behavior?

An active chat must never disappear or appear deleted without an explicit user action.

If thread hydration, renderer state, sidebar indexing, or history loading fails:

• the task should remain visible;
• the existing conversation history should be recoverable;
• the UI should show a bounded error/retry state rather than presenting an empty or deleted chat;
• the desktop list and the underlying task inventory should reconcile automatically.

Additional information

Impact in the latest occurrence:

• the user believed the chat had been deleted again;
• the current implementation state had to be reconstructed from retained agent context and local diffs;
• local code changes were still present, so the workspace itself was not deleted;
• the underlying task inventory reported the task as active immediately after the UI disappearance.

This appears related to task visibility/indexing reports such as #33579, but differs because it affected the currently active Windows task during ongoing work and has recurred.

No task IDs, task titles, repository names, local paths, account identifiers, chat content, code, secrets, or screenshots are included in this public report.