Recent turns inside an existing task disappear after restarting Codex Desktop #42245

What version of the Codex App are you using (From “About Codex” dialog)?

26.825.51511 (build 7377)

What subscription do you have?

Pro

What platform is your computer?

Apple Silicon Mac

What issue are you seeing?

Environment

• Codex Desktop: 26.825.51511 (build 7377)
• macOS: 26.6.2 (25G83)
• Platform: Apple Silicon Mac
• Date observed: September 2026

Problem

After quitting and reopening Codex Desktop, an existing task still appears
normally in the sidebar, but the recent part of its conversation history is
missing.

This is not a missing-task or sidebar-filtering issue. The task opens
successfully, but its transcript appears to stop at an earlier point. Multiple
recent user messages, assistant responses, tool calls, and generated artifacts
are no longer shown in the task UI.

Steps to reproduce

1. Use a single Codex task for a long-running project with many conversation
   turns and tool calls.
2. Allow the task to continue across multiple context-compaction cycles.
3. Wait for the current response to complete.
4. Quit Codex Desktop.
5. Reopen Codex Desktop and open the same task.
6. Observe that the task is present, but some of its most recent conversation
   turns are missing.

The problem has occurred after more than one application restart.

Expected behavior

The task should reopen with every completed conversation turn visible, up to
the most recent completed message.

Actual behavior

The task reopens at an older point in its history. Recent completed messages
are absent from the UI, making the task appear to have reverted to an earlier
state.

Local evidence

The missing turns were found in the task's local session transcript under the
Codex session storage directory. Generated artifact files referenced by those
turns also still existed on disk.

This suggests that, in this occurrence, the underlying transcript was not
deleted. The desktop app appears to be loading, replaying, or rendering only
part of the persisted task history.

No local Codex database, session transcript, or index file was manually
modified during diagnosis.

Frequency and impact

• Reproduced after restarting Codex Desktop.
• Affects long-running tasks.
• A substantial amount of recent project context can disappear from the UI.
• Missing content can sometimes be recovered manually from the local session
  transcript, but this is difficult and error-prone.

Possibly related issue

This appears to match:
#15349

The possible relationship with context compaction is only a hypothesis. I do
not have enough evidence to identify compaction as the root cause.

What steps can reproduce the bug?

1. Use a single Codex task for a long-running project with many conversation
   turns and tool calls.
2. Allow the task to continue across multiple context-compaction cycles.
3. Wait for the current response to complete.
4. Quit Codex Desktop.
5. Reopen Codex Desktop and open the same task.
6. Observe that the task is present, but some of its most recent conversation
   turns are missing.

What is the expected behavior?

No response

Additional information

No response