@tobiasharth

What happened?

On iOS, after toggling the OS appearance (Control Center light ↔ dark), some views with theme-driven Uniwind classes (most visibly bg-surface / bg-background) stay rendered with the previous theme's color until they receive any interaction (touch, scroll, layout change).

As far as I can tell from visual inspection, backgroundColor is the property that fails most consistently — text and border colors on the same view appear to update correctly in the cases I checked, but I have not exhaustively audited every property, so I can't rule out that others are affected too.

A single appearance flip is enough; rapidly flipping while navigating amplifies the rate but isn't required.

Swapping the navigation library to expo-router (with byte-identical screen content, same Uniwind classes, same Reanimated animations, same providers) eliminates the bug. The two branches in the linked repo are the comparison — react-navigation native-stack reproduces, expo-router does not.

Diagnostic via UniwindDiagnostics.onShadowTreeUpdate confirms Uniwind itself pushes the new theme values correctly (currentTheme, colorScheme, all nodes traversed). The miss appears to be on the iOS commit side — the new value reaches the shadow tree but isn't committed to the affected CALayer until a secondary trigger.

Already ruled out:

• react-native-screens freeze path (enableFreeze(false) + freezeOnBlur:false on both navigators) — still reproduces.
• StyleSheet vs className on the affected screens — no effect.

Here a short screen recording of the List → Detail → back flow with the appearance flip in step 2 — the stale bg-surface cards on the returned List screen are the clearest visual proof.

Simulator.Screen.Recording.-.iPhone.16.Pro.-.2026年04月27日.at.14.04.36.mov

Steps to Reproduce

1. Check out the react-navigation-bug-repro branch of the linked repo, then pnpm install && pnpm expo prebuild && pnpm ios.
2. Open the List tab (Animated.FlatList with a sliding header overlay backed by bg-surface).
3. Toggle the iOS Simulator's appearance once via Control Center (Cmd+Shift+A — not Settings → Display).
4. Tap any card to push into Detail, then tap Back.
5. The cards on the returned List screen still render the previous theme's bg-surface color. Scrolling the FlatList or tapping a card forces a re-render and the colors snap to the correct theme.
6. Switch to the expo-router-fix-reference branch (same screens, only navigation layer differs) and repeat — bug does not reproduce.

Snack or Repository Link (Optional)

https://github.com/tobiasharth/uniwind-theme-flip-repro

Uniwind version

1.1.0

React Native Version

0.83.6

Platforms

iOS

Expo

Yes

Additional information

• I've searched for similar issues in this repository and found none
• I am a Uniwind Pro user