Cannot find how to turn off Fast mode in Codex app on macOS Apple Silicon
What version of the Codex App are you using (From “About Codex” dialog)?
Version 26.422.62136 (2180)
What subscription do you have?
Business
What platform is your computer?
Darwin 25.4.0 arm64 arm
What issue are you seeing?
I cannot find a clear way to turn off Fast mode in the Codex app UI on macOS. The model selector shows a lightning icon next to 5.5 High, but there is no visible menu option to disable Fast mode.
<img width="492" height="452" alt="Image" src="https://github.com/user-attachments/assets/5885b54f-fc92-43d8-b44c-63aec78cf957" />
What steps can reproduce the bug?
Uploaded thread: 019c4340-195a-79b3-84b0-908cb61110fc
Steps to reproduce:
- Open the Codex app on macOS Apple Silicon / M2 Pro.
- Open a local workspace.
- Select GPT-5.5 with High intelligence.
- Observe that the model selector shows
⚡ 5.5 High. - Click the model selector.
- The menu only shows Intelligence options: Low, Medium, High, Extra High, plus model choices such as GPT-5.5 / GPT-5.4 / Other models.
- There is no visible option to turn Fast mode off.
- Try typing
/fast offin the Codex app chat composer. - The app treats
/fast offas a normal instruction, not as a command. - Open Codex CLI separately and run
/fast off. - CLI reports
Fast mode is off, and~/.codex/config.tomlcontains:
```toml
[notice]
fast_default_opt_out = true
- Return to the Codex app UI.
- The model selector still shows the lightning icon next to 5.5 High.
What is the expected behavior?
The Codex app should provide a clear UI control to turn Fast mode on or off.
The UI should also clearly show whether Fast mode is actually active. If the lightning icon only means that the selected model supports Fast mode, the app should explain that. If it means Fast mode is active, it should disappear or change when Fast mode is off.
The app should also make it clear whether Fast mode settings are shared with Codex CLI or separate from the app UI.
Additional information
This is confusing because Codex CLI reports Fast mode is off, but the Codex app model selector still shows ⚡ 5.5 High.
I could not find any Fast mode toggle in the app UI. The /fast off command works in Codex CLI but not in the Codex app composer.
Feedback ID / uploaded thread:
019c4340-195a-79b3-84b0-908cb6110fc
This issue has 3 comments on GitHub. Read the full discussion on GitHub ↗