Liquid Glass header shadows incorrectly invert when FlatList has inverted={true} on iOS 26

Comienza con el reproductor obligatorio de Snack y compara el comportamiento del header en casos de FlatList invertidos y no invertidos en iOS. Usa las configuraciones de headerTransparent y ViewController, incluido el caso scaleY: -1, como puntos de entrada para la investigación. Se considera terminado cuando el header transparente conserva la sombra normal y el degradado de desenfoque, y el contenido debajo se oscurece correctamente.

Description

Expected Behavior

When using inverted={true} FlatList, the header shadow/blur should maintain its normal appearance with proper content darkening underneath the transparent header.

Actual Behavior

Liquid Glass interface automatically detects the FlatList inversion and incorrectly inverts the header blur gradient. This causes:

1. All visible content under the header becomes properly darkened (incorrect)
2. All content that should be darkened under the header remains fully transparent (incorrect)

The shadow/blur gradient is effectively inverted, creating the opposite visual effect.

migrated from https://github.com/software-mansion/react-native-screens/issues/3293

Steps to reproduce

1. Setting up headerTransparent: true if using Navigation OR add native elements to ViewController (Searchbar etc.)
2. Add a FlatList with inverted={true} OR apply transform: [{ scaleY: -1 }]
3. Scroll the list and observe the header shadow behavior
4. Compare with a non-inverted FlatList

React Native Version

0.81.4

Affected Platforms

Runtime - iOS

Output of npx @react-native-community/cli info

System:
  OS: macOS 26.0.1
  CPU: (11) arm64 Apple M3 Pro
  Memory: 184.17 MB / 18.00 GB
  Shell:
    version: "5.9"
    path: /bin/zsh
Binaries:
  Node:
    version: 22.14.0
    path: /Users/vasgen/.nvm/versions/node/v22.14.0/bin/node
  Yarn:
    version: 3.6.1
    path: /Users/vasgen/.nvm/versions/node/v22.14.0/bin/yarn
  npm:
    version: 10.9.2
    path: /Users/vasgen/.nvm/versions/node/v22.14.0/bin/npm
  Watchman:
    version: 2025.03.03.00
    path: /opt/homebrew/bin/watchman
Managers:
  CocoaPods:
    version: 1.16.2
    path: /opt/homebrew/bin/pod
SDKs:
  iOS SDK:
    Platforms:
      - DriverKit 25.0
      - iOS 26.0
      - macOS 26.0
      - tvOS 26.0
      - visionOS 26.0
      - watchOS 26.0
  Android SDK:
    API Levels:
      - "34"
    Build Tools:
      - 29.0.2
      - 32.0.0
      - 34.0.0
    System Images:
      - android-34 | Google Play ARM 64 v8a
    Android NDK: Not Found
IDEs:
  Android Studio: 2024.2 AI-242.23339.11.2421.12483815
  Xcode:
    version: 26.0.1/17A400
    path: /usr/bin/xcodebuild
Languages:
  Java:
    version: 17.0.14
    path: /usr/bin/javac
  Ruby:
    version: 2.6.10
    path: /usr/bin/ruby
npmPackages:
  "@react-native-community/cli": Not Found
  react:
    installed: 19.1.0
    wanted: 19.1.0
  react-native:
    installed: 0.81.4
    wanted: 0.81.4
  react-native-macos: Not Found
npmGlobalPackages:
  "*react-native*": Not Found
Android:
  hermesEnabled: Not found
  newArchEnabled: Not found
iOS:
  hermesEnabled: Not found
  newArchEnabled: Not found

Stacktrace or Logs

-

MANDATORY Reproducer

https://snack.expo.dev/@whidrubeld/liquid-glass-header-shadows-incorrectly-invert-when-flatlist-has-inverted

Screenshots and Videos

Example of behavior

ViewController setting up