[app] Side chats provide no chance to disable “Use memory” before it is locked

Start by tracing the macOS app's side-chat/sidebar creation flow and the Task Memory settings dialog, reproducing the issue with the Chinese locale if useful. Verify when the conversation becomes locked and how Use memory and Generate memory are represented. Done means a side chat can be created without existing memories, while the two controls remain independent.

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

26.707.91948 (build 5440; detected from the installed macOS app bundle)

What subscription do you have?

ChatGPT subscription (exact tier not confirmed; the issue reproduces in the client UI before any model request)

What platform is your computer?

Darwin 25.4.0 arm64 arm (macOS 26.4.1)

What issue are you seeing?

When a Codex side chat is opened, Task Memory → Use memory is already enabled and disabled, so it cannot be turned off.

The dialog says the setting cannot be changed after the conversation starts, but the side-chat flow does not provide any opportunity to configure it before the chat is considered started. This makes it impossible to create a side chat that does not read existing memories.

This is specifically about the two separate controls shown in the Task Memory dialog:

• Use memory (使用记忆): enabled, but the toggle is disabled. Helper text: 对话开始后无法更改 (“Cannot be changed after the conversation starts”).
• Generate memory (生成记忆): remains independently editable.

What steps can reproduce the bug?

1. Open the Codex side-chat/sidebar experience in the macOS app.
2. Create or open a side chat.
3. Open Task Memory settings.
4. Try to turn off Use memory.
5. Observe that the toggle is enabled but disabled immediately, with no earlier point in the side-chat flow where it could have been changed.

No code snippet, session ID, token usage, or context-window usage is required; this is a client-side UI/flow issue.

What is the expected behavior?

The user should have a way to create a side chat without using existing memories.

For example, either:

• expose Use memory before the first side-chat message starts the conversation, or
• provide a Start side chat without memory action, or
• allow the toggle to change until the first user message is actually submitted.

The Use memory and Generate memory choices should remain independent.

Additional information

The issue was reproduced with the UI locale set to Chinese. A screenshot shows Use memory switched on but disabled while Generate memory remains editable.

A search of open and closed issues in openai/codex did not find an existing report for this side-chat-specific flow.