/realtime fails with 403 on Windows PowerShell: failed to connect realtime websocket

Summary

/realtime fails immediately with:

stream disconnected before completion: failed to connect realtime websocket: HTTP error: 403 Forbidden

This happens even after re-authenticating with ChatGPT device auth.

Environment

• OS: Windows (PowerShell)
• Codex CLI: 0.106.0
• Install method: npm install -g @openai/codex
• Auth mode: ChatGPT login (codex login --device-auth)
• Working directory example: C:\Users\27613\OneDrive\바탕 화면\codex (contains non-ASCII path segments)

Reproduction

1. Run codex
2. Re-login with codex login --device-auth
3. In TUI, run /realtime
4. Error appears immediately:

• stream disconnected before completion: failed to connect realtime websocket: HTTP error: 403 Forbidden

Current feature flag state

From codex features list:

• realtime_conversation: under development, enabled (true in config)
• responses_websockets_v2: under development, enabled (true in config)
• responses_websockets: disabled (false)

Expected behavior

/realtime should connect successfully (or provide a clear actionable message if account rollout/permission is missing).

Actual behavior

Realtime websocket handshake fails with HTTP 403 and conversation does not start.

Additional context

• Re-login did not resolve the issue.
• I am using Windows + PowerShell.
• Could this be account/rollout gating for realtime_conversation / websocket v2?
• If so, can CLI detect this case and show a clearer message than generic websocket 403?

Question to maintainers

Is this a known gating behavior, or should this work on 0.106.0 for all ChatGPT-authenticated users?