Adding onViewableItemsChanged to SectionList changes the items passed to each section's keyExtractor

Description

We wrote a SectionList component where each section defines it's own keyExtractor. One of the sections uses a key from a nested object in each item in the section. It broke when we wanted to add visibility tracking to the section list, and it seems like the section objects are being run through the keyExtractor but only when onViewableItemsChanged prop is provided.

I expect that only items within each section should be run through the section's keyExtractor function, and that the behavior is consistent regardless of what props are provided.

Steps to reproduce

1. Open expo snack linked below
2. Run it on android or iOS device and observe it works
3. Uncomment the onViewableItemsChanged line from the SectionList and observe the break

React Native Version

0.75.3

Affected Platforms

Runtime - Android, Runtime - iOS

Output of npx react-native info

See expo snack for reproduction

Stacktrace or Logs

Cannot read property 'id' of undefined

Reproducer

https://snack.expo.dev/V1Ad0VTld860Zdt8n-qb7

Screenshots and Videos

Inizia con l’Expo Snack collegato e riproduci il problema su Android o iOS attivando e disattivando la prop onViewableItemsChanged di SectionList. Traccia il modo in cui il monitoraggio della visibilità invoca section keyExtractor e verifica che gli vengano passati in modo coerente solo gli elementi all’interno di ogni sezione, con o senza quella prop.