Codex Firefox Bridge

Install the native-messaging companion used by Codex Computer Use for Firefox and Zen Browser:

npx --yes codex-firefox-bridge install

The command downloads the matching bridge from the GitHub release, verifies its published SHA-256 checksum, installs it in the current user's application-data directory, registers it with Firefox and Zen Browser, and runs a diagnostic. The doctor and uninstall commands verify and remove the installation.

On Linux the binary is installed under $XDG_DATA_HOME/Codex Firefox Bridge (default ~/.local/share/Codex Firefox Bridge). The required native-host manifest is written to ~/.mozilla/native-messaging-hosts/, which both unconfined Firefox and Zen Browser read. A second manifest is written to ~/.zen/native-messaging-hosts/ on a best-effort basis when that path is writable; current Zen Linux builds read the Mozilla registration, so the .zen copy is optional and never fails installation or diagnostics.

npx --yes codex-firefox-bridge doctor
npx --yes codex-firefox-bridge uninstall

This is an independent compatibility project, not an official OpenAI or Mozilla package. The official Codex Chrome integration must already be installed because the bridge delegates to its local OpenAI host.

Why is this needed?

Firefox extensions cannot start arbitrary local processes or reuse a native host registered for a Chrome extension. Codex currently exposes its browser connection through that native-host path, rather than a supported Firefox API or authenticated local endpoint, so this bridge provides the required per-user OS registration and delegates to the official host.

If OpenAI opens an official Firefox path or another supported local connection, we'd love to adopt it and simplify or remove this companion :)