Codex 0.140.0 adds a workspace file browser to preview and link files into prompts, plus a directory picker for starting new threads. You can now expand or collapse all diffs at once when reviewing changes, and approve MCP actions for the current chat or all chats. LaTeX rendering now works in Codex messages and plans. Session deletion is now permanent with confirmation safeguards, and /import lets you selectively bring setup, project config, and recent chats from Claude Code. Typing @ opens a unified mentions menu for files, plugins, and skills by default.