[macOS] ChatGPT mode missing / selector stuck on Codex in 26.901.41600 while web works

App version

ChatGPT 26.901.41600 (app reports this is the newest version available)

Platform

macOS desktop app

Issue

The desktop app is effectively stuck in Codex mode. The top-left selector shows Codex, but ChatGPT is not available/does not switch. The corresponding selector in Settings is also stuck on Codex.

The sidebar shows Codex-specific navigation (New chat, Pull requests, Sites, Scheduled, Plugins) and does not expose the normal ChatGPT interface.

Quick/Mini Chat can accept a test message and reports “Received”, but the main desktop UI remains in Codex and does not expose normal ChatGPT.

The same ChatGPT account works normally at chatgpt.com, including normal Chat and existing conversations.

Troubleshooting already performed

• Fully removed the desktop app
• Removed cached/local app files
• Downloaded and reinstalled the app
• Confirmed the app updater says 26.901.41600 is current
• Opened an existing conversation and tried the selector again
• Tested the same account on chatgpt.com; web works normally

None of the desktop troubleshooting changed the behavior.

Expected behavior

Per the current desktop-app documentation, the top-left selector should allow switching between ChatGPT and Codex, and normal Chat should be available under ChatGPT.

Related reports

This appears related to recent reports such as #42322 (ChatGPT/Codex selector unresponsive) and #42516 (Chat mode missing after a 26.901-series update), but this reproduction is specifically on macOS build 26.901.41600 and persists after a clean reinstall.

Reproduce the issue in the macOS desktop app on build 26.901.41600, checking the top-left and Settings selectors, Quick/Mini Chat, and a clean reinstall. Trace the desktop mode-selection flow and compare it with the working web behavior; done means ChatGPT is available and selectable alongside Codex for affected accounts.