[iOS] Horizontal list bounces vertically ( New Year magic )

Description

Sometimes after some user interactions, the horizontal list starts bouncing vertically. (Gif attached) We have two different applications - it was caught on both.

React Native version:

0.63.4 ( reproduced on 0.63.3 )

Steps To Reproduce

Reproduced on the real device only! In my case:

1. Go to another tab
2. Open a list with items that are depending on the same data as items from the first tab
3. Try to change some data
4. Items re-render on the first tab also
5. List starts bouncing

Moreover, if I swap this List with another one the issue starts to reproduce on the new one.

Expected Results

The horizontal list is not bouncing vertically

Snack, code example, screenshot, or link to a repository:

I’ve tried to create a reproducible demo but no luck 😭

Deps:

"@react-native-community/async-storage": "^1.12.0",
    "@react-native-community/masked-view": "^0.1.10",
    "@react-native-mapbox-gl/maps": "^8.1.0-rc.9",
    "@react-navigation/bottom-tabs": "^5.11.2",
    "@react-navigation/devtools": "^5.1.17",
    "@react-navigation/native": "^5.6.1",
    "@react-navigation/stack": "^5.12.8",
    "@types/lodash": "^4.14.157",
    "@types/react-native-snap-carousel": "^3.8.2",
    "@types/react-redux": "^7.1.9",
    "axios": "^0.19.2",
    "husky": "^4.2.5",
    "i18next": "^19.5.1",
    "lint-staged": "^10.2.11",
    "lodash": "^4.17.19",
    "react": "16.13.1",
    "react-i18next": "^11.7.0",
    "react-native": "0.63.4",
    "react-native-fast-image": "^8.3.2",
    "react-native-geolocation-service": "^5.0.0",
    "react-native-gesture-handler": "^1.6.1",
    "react-native-linear-gradient": "^2.5.6",
    "react-native-permissions": "^2.1.5",
    "react-native-reanimated": "^1.13.0",
    "react-native-render-html": "^4.2.3",
    "react-native-safe-area-context": "^3.0.7",
    "react-native-screens": "^2.9.0",
    "react-native-snap-carousel": "^3.9.1",
    "react-native-splash-screen": "^3.2.0",
    "react-native-svg": "^12.1.0",
    "react-native-svg-transformer": "^0.14.3",
    "react-native-ultimate-config": "^3.2.3",
    "react-native-webview": "^10.9.0",
    "react-redux": "^7.2.0",
    "reanimated-bottom-sheet": "^1.0.0-alpha.22",
    "redux": "^4.0.5",
    "redux-devtools-extension": "^2.13.8",
    "redux-persist": "^6.0.0",
    "redux-saga": "^1.1.3",
    "reselect": "^4.0.0",
    "typesafe-actions": "^5.1.0"

Workaround:

1. bounces={false}
2. update all List items on tab focus via key prop replacement

[jacobp100]

I assume HomeSectionBar has the titles too?

One thing that might work is putting contentContainerStyle={{maxHeight: '100%'}} on the horizontal FlatList - or set an explicit height if you know it

[liamjones]

This still occurs for us occasionally, even in 0.66