Conversation history disappears from the Codex desktop UI after compaction

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

0.151.0-alpha.7.2

What subscription do you have?

Plus

What platform is your computer?

Darwin 25.6.0 arm64 arm

What issue are you seeing?

A long-running conversation in the Codex desktop app has lost most of its visible history. Messages that were previously displayed, including messages sent recently, no longer appear when opening the task.

The messages have not actually been deleted: the complete conversation is still present in the local session transcript. This appears to be a UI rendering or session-loading issue that occurred after the conversation was compacted.

What steps can reproduce the bug?

• Open a task in the Codex desktop app.
• Continue using the same task until the conversation becomes long enough to trigger context compaction.
• Close or navigate away from the task.
• Open the task again.
• Observe that only part of the conversation is displayed.
• Send additional messages and reopen the task.
• Some of the newly sent messages may also be missing from the visible history.

What is the expected behavior?

Expected behavior

The complete user-visible conversation should remain accessible after context compaction. Compaction may summarize context internally for the model, but it should not remove or hide messages from the conversation UI.

Actual behavior

A significant portion of the conversation disappears from the UI. The task appears incomplete or truncated, even though the missing messages remain stored in the local JSONL session transcript.

This makes it look as though the conversation and recent work have been permanently lost.

Additional information

Additional information

• Session/comment ID: 01a05d90-8d56-73c3-96c8-58db713d7f6f
• Codex version: 0.151.0-alpha.7.2
• Application: Codex desktop
• Session origin: codex_work_desktop
• Session source: chatgpt_handoff
• Operating system: macOS 26.6.2 (Build 25G83)
• Architecture: Apple Silicon (arm64)
• The local transcript still contains the missing messages.
• An internal compaction event appears in the session before the history-display problem.
• The issue affects both older messages and messages sent after the conversation was reopened.

Impact

The user cannot reliably access previous research, decisions, links, or recent responses through the interface. Because the UI gives no indication that the messages still exist locally, it creates the impression of permanent data loss.

No source file or test is named. Start by tracing Codex desktop task history loading and rendering around the internal compaction event, comparing displayed messages with the local JSONL session transcript. Done means the complete conversation, including messages sent after reopening, remains visible after compaction.