All platforms · 8 min · Upstream checked July 17, 2026

Fix a Codex theme after an app update

Diagnose selector drift, stale injected state, and version mismatch without patching the official application.

Platform behavior can change. Compare this guide with the original repository at commit 26c6c410e0e0.
01Restore the previous theme session
02Confirm Codex works stock
03Update from the original upstream
04Reinstall and verify every route

First isolate the update from the theme

Restore the theme and open Codex normally. If the official appearance also fails, the issue is outside the theme layer. If stock Codex works, record the exact Codex version, platform, architecture, upstream commit, and the first route where the themed UI differs.

Why updates can break a theme

External themes depend on renderer structure and DOM markers. Codex can rename or move those elements during an update, leaving a background visible while cards, composer, or sidebar styling disappears. A stale injector can also target a renderer that no longer matches the expected identity.

Repair with a fresh, reviewable state

Pull or download the current original repository, read its changelog and platform guide, then rerun the documented install and verification flow. Do not edit the signed application package as a shortcut. Verify Home, Task, Diff, menus, composer, and restore before keeping the theme active.

A screenshot that looks correct is insufficient; buttons, menus, project selection, scrolling, and the composer must still work.

Completion checklist

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