ScrollView with centerContent={true} is not working properly

Description

• On ScreenViewScreen1, the contentCenter={true} property
• On ScreenViewScreen2, the contentCenter={false} property
• On ScreenViewScreen2, the content remains centered during ternary screen swapping

Testing was performed on 3 versions of React Native:

• 0.79.1
• 0.78.2
• 0.77.2

Detailed problem result in README.md in the repository.

Steps to reproduce

1. In the repository go to the desired version of React Native
2. Install dependencies and run the project following the instructions in README.md of the project
3. Try to change the parameters in src/App.tsx

React Native Version

0.79.1

Affected Platforms

Runtime - iOS

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

System:
  OS: macOS 15.4.1
  CPU: (8) arm64 Apple M1 Pro
  Memory: 117.52 MB / 16.00 GB
  Shell:
    version: "5.9"
    path: /bin/zsh
Binaries:
  Node:
    version: 22.14.0
    path: ~/.nvm/versions/node/v22.14.0/bin/node
  Yarn: Not Found
  npm:
    version: 11.2.0
    path: ~/.nvm/versions/node/v22.14.0/bin/npm
  Watchman:
    version: 2025.04.07.00
    path: /opt/homebrew/bin/watchman
Managers:
  CocoaPods: Not Found
SDKs:
  iOS SDK:
    Platforms:
      - DriverKit 24.4
      - iOS 18.4
      - macOS 15.4
      - tvOS 18.4
      - visionOS 2.4
      - watchOS 11.4
  Android SDK: Not Found
IDEs:
  Android Studio: 2024.2 AI-242.23726.103.2422.13103373
  Xcode:
    version: 16.3/16E140
    path: /usr/bin/xcodebuild
Languages:
  Java:
    version: 17.0.14
    path: /usr/bin/javac
  Ruby:
    version: 2.7.8
    path: /Users/alex/.rbenv/shims/ruby
npmPackages:
  "@react-native-community/cli":
    installed: 18.0.0
    wanted: 18.0.0
  react:
    installed: 19.0.0
    wanted: 19.0.0
  react-native:
    installed: 0.79.1
    wanted: 0.79.1
  react-native-macos: Not Found
npmGlobalPackages:
  "*react-native*": Not Found
Android:
  hermesEnabled: true
  newArchEnabled: true
iOS:
  hermesEnabled: true
  newArchEnabled: true

Stacktrace or Logs

-

Reproducer

https://github.com/astrahov/React-Native-ScrollView-contentCenter-bug

Screenshots and Videos

https://github.com/user-attachments/assets/1b08fd74-2f07-4d64-a795-8a3fc0a2f7fd

Start with the linked reproducer, following its README.md setup instructions and inspecting src/App.tsx. Compare the centerContent={true} and centerContent={false} cases across the listed React Native versions, including the ternary screen swap; done means the observed iOS ScrollView behavior matches the intended setting.