Codex macOS app bug: new chats fail on first message with serialization error
ZhangLiangchen · ghdev · 2026-10-21
OpenAI's Codex desktop app on macOS (version 26.1016.51333) has a bug where sending the first message in any new chat fails with "Cannot serialize value (couldn't stringify value)".
- Reproduction: open a project, create a new chat, and send a minimal plain-text message like "hello" — no attachments or file references needed
- Reproduces in both newly added projects and new chats within existing projects
- The error appears after sending the first message, not when creating the chat
- The reporter suspects a recent-version regression, but this isn't confirmed by testing an older build; logs and restart results are still pending
The GitHub issue has drawn 26 reactions and 22 comments.
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