Codex App: Conversation Forking & Floating Windows

What's New in v260212

The February 12 update to the Codex desktop app — versioned as v260212 — ships several user-facing features alongside support for the same-day GPT-5.3-Codex-Spark model launch.

GPT-5.3-Codex-Spark Model Support

The most prominent addition is native support for GPT-5.3-Codex-Spark, allowing Codex app users to switch to the new real-time coding model directly from within the app interface. Users on ChatGPT Pro can now experience the model's 1,000+ tokens-per-second inference without switching to the CLI.

Conversation Forking

Version v260212 introduces conversation forking, allowing users to branch from any prior point in a conversation and explore an alternative direction without losing their original thread. This is particularly useful during iterative development sessions where a user wants to try a different approach mid-conversation.

Floating Pop-Out Window

A new floating pop-out window feature lets users detach an active conversation thread into a separate portable window. This window can be repositioned anywhere on the desktop — useful for front-end development workflows where a developer wants to keep the AI thread visible near a browser, design preview, or editor while working.

Windows Alpha Signups

Since launch, the Codex app has been macOS-only. Version v260212 opens alpha testing signups for Windows, marking the first concrete step toward cross-platform availability. OpenAI has cited the need for robust sandboxing primitives as the reason Windows support lagged, and the alpha program represents the beginning of that rollout.