Remote host switch shows Mac Studio connected, but new chats still run locally on client

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

26.609.41114

What subscription do you have?

ChatGPT Plus

What platform is your computer?

Client: MacBook Air / macOS Monterey 12.7.6, Build 21H1320 Host: Mac Studio, macOS Tahoe / 26 Both running Codex 26.609.41114

What issue are you seeing?

I’m trying to use Codex on my MacBook Air to control Codex on my Mac Studio.

In Settings on the MacBook Air, I can select the remote host Mac-Studio.mynet. It shows a green connected dot. I can also view host-specific settings for the Mac Studio, such as Configuration, MCP servers, Hooks, Environments, Worktrees, and Archived chats.

However, when I click “Back to app”, the main chat UI does not switch to the Mac Studio runtime. It still shows my local MacBook Air chats/projects, and new prompts run locally on the MacBook Air.

Evidence: after selecting Mac-Studio.mynet in Settings, clicking Back to app, starting a new chat, and asking Codex to run:

hostname
sw_vers
pwd

The output is:

Brians-Air.mynet
ProductName: macOS
ProductVersion: 12.7.6
BuildVersion: 21H1320
/Users/Brian/Dropbox/Trading/StockTalk/Discord Download

Expected output would be the Mac Studio hostname and macOS Tahoe / 26.

What steps can reproduce the bug?

On Mac Studio, enable Settings → Connections → Control this Mac.
On MacBook Air, go to Settings → Connections → Control other devices.
Connect to Mac-Studio.mynet.
Confirm it shows a green connected dot.
In Settings on the MacBook Air, use the top-left host dropdown to select Mac-Studio.mynet.
Confirm Mac Studio-specific settings are visible.
Click “Back to app”.
Start a new chat.
Ask Codex to run:

hostname
sw_vers
pwd

The command runs on the MacBook Air instead of the Mac Studio.

What is the expected behavior?

After selecting Mac-Studio.mynet as the active host, clicking “Back to app” should make new chats/prompts run on the Mac Studio host. The main chat UI should show/use the Mac Studio’s threads, projects, worktrees, filesystem, and runtime.

Additional information
Both machines are signed into the same ChatGPT account and are running the same Codex version: 26.609.41114.

The remote connection appears to work in Settings, because the MacBook Air can view Mac Studio-specific settings. The failure seems to be that the selected remote host is not carried through into the main chat UI/runtime.

This may be related to the client being on macOS Monterey 12.7.6.

Additional information

_No response_