Prompt consumed as steering input during compaction instead of being queued (experimental steer conversation enabled)

What version of Codex is running?

codex-cli 0.87.0

What subscription do you have?

Pro

Which model were you using?

gpt-5.2-codex xhigh

What platform is your computer?

MacOS

What terminal emulator and version are you using (if applicable)?

TERM_PROGRAM is vscode, version 1.109.0-insider (TERM is xterm-256color).

What issue are you seeing?

When the experimental "steer conversation" feature is enabled and context compaction is in progress, entering a prompt by pressing Enter causes the prompt to be consumed/digested as a steering prompt for the compaction process itself.

However, context compaction cannot be steered, so this behavior results in the prompt being lost/misused rather than being queued for execution after compaction completes.

What steps can reproduce the bug?

1. Enable the experimental "steer conversation" feature in the configuration
2. 2. Run /compact
3. 3. While compaction is actively occurring, type a prompt in the input field
4. 4. Press Enter to submit the prompt
5. 5. Observe that the prompt is consumed as steering input for the compaction process rather than being queued for later execution

What is the expected behavior?

The prompt should be queued and executed after the compaction process completes, not consumed as steering input for the compaction itself.

Since compaction is not a steerable operation, prompts entered during compaction should be buffered/queued for subsequent execution rather than being misinterpreted as steering attempts. Alternatively, they should be rejected with an error message.

Additional information

This bug specifically occurs when the experimental "steer conversation" feature is enabled. The interaction between the steering prompt mechanism and the compaction process appears to incorrectly interpret user prompts entered during compaction as steering directives.

The impact is that users lose their prompts when entering them during compaction, which can be frustrating and disruptive to workflow.