TUI: Ctrl+C while editing a previous message appends thread_rolled_back and hides the message

Summary

In the interactive Codex CLI TUI, pressing Ctrl+C while editing a previous message appears to be handled as a thread rollback instead of a harmless edit cancellation. The selected previous message disappears from the TUI/resumed conversation, while the original message is still physically present in the session JSONL.

Version

Originally observed while using codex-cli 0.142.0.

After updating, local codex --version currently reports codex-cli 0.142.5; The display bugs still exist, but I have not yet confirmed the bug still reproduces from start on 0.142.5.

Reproduction Steps

1. Start or resume an interactive Codex CLI TUI session.
2. Press Esc to select a previous user message.
3. Press Enter to edit that previous message.
4. Press Ctrl+C to quit/cancel the edit.
5. Observe the TUI transcript or resume/fork the session.

Actual Behavior

The selected previous message disappears from the TUI transcript / reconstructed conversation.

Expected Behavior

Canceling edit mode should discard only the temporary edit buffer. The original previous message should remain visible and the logical conversation should remain unchanged.

JSONL Investigation

The original message is still physically present in the saved session file under ~/.codex/sessions/.../*.jsonl, so the message content is not deleted from disk.

However, after each reproduction, the JSONL has an appended event like:

{"type":"event_msg","payload":{"type":"thread_rolled_back","num_turns":1}}

In my affected session, each thread_rolled_back event corresponded to one disappeared previous message. Removing those rollback events from a backed-up JSONL session file restored the missing messages when resuming the session.

Hypothesis

Ctrl+C from previous-message edit mode is taking the rollback path instead of the edit-cancel path. This likely affects the reconstructed logical thread, not just the current TUI display, because the rollback event is replayed from JSONL on resume/fork.