hey there! what you are seeing is the following:

• the splash screen is displayed when you launch the app
• the splash screen is then hidden and the app is loaded, bundling begins

we aren't actually showing the splash screen for the app outside of the initial launch, the flickering (splash -> black background -> your app) is the app loading.

cc @alanjhughes to verify that we display splash appropriately in expo-dev-client in the sdk 52 changes

Yes, and this only happens after expo-dev-client is added. It seems like the splash screen somehow gets displayed wrongly when the bundle begins. Any update on this?

@johnsiah - this shouldn't impact any production use case, so we aren't prioritizing it at the moment, but @alanjhughes will verify that it will be resolved by sdk 52

@brentvatne got it. By the way, we also saw this reproducible in the production app when we built the production profile. Exactly the same as the demo video display above.

@johnsiah - can you elaborate on what you mean by that? in #30729 (comment) i mentioned that the splash screen shows as expected on the initial app launch, it just doesn't show when you reload within expo-dev-client. if your splash screen is just hiding too early, you may need to delay hiding it manually and hide it when you know your app is ready. eg: https://docs.expo.dev/versions/latest/sdk/splash-screen/#usage

@brentvatne Note that the bare expo project for testing this issue doesn't install the expo-splash-screen yet, just a basic expo new project setup adding expo-dev-client.

The reason for not adding expo-splash-screen is that we'll be using a library like react-native-bootsplash for the splash screen. I've tried using back expo-splash-screen and it seems like it fixed the issue, but if we were to choose an alternative library or manual splash screen handling or even not adding splash screen at all, it seems like there's some logic in expo-splash-screen sort of handling this expo-dev-client issue reported above.

More interesting is that when I build a release internal preview using the profile below, it should be building a release build but the same flickering is still there.

// eas.json
  "build": {
    "preview": {
      "distribution": "internal"
    }
  },

Pasting all my dependencies here for more clarity.

  "dependencies": {
    "expo": "51.0.28",
    "expo-build-properties": "~0.12.5",
    "expo-dev-client": "4.0.23",
    "expo-status-bar": "~1.12.1",
    "react": "18.2.0",
    "react-dom": "18.2.0",
    "react-native": "0.74.5"
  },
  "devDependencies": {
    "@babel/core": "^7.20.0"
  },

The same black flicker/flash is reproducible in production scenarios.

Here's a minimal repro: https://github.com/matthieugicquel/bootsplash-black-flash

The minimal setup to have the issue seems to be (I usually don't notice a black flicker with just this):

• react-native-bootsplash setup according to their docs (this includes disabling autolinking for expo-splash-screen
• release build
• expo-updates installed, enabled, with checkAutomatically: "ON_LOAD" (the default value)

To make the black screen visible every time, you can add:

• fallbackToCacheTimeout: 10000 (this is included in the repro above)
• and a slow network (I use the network link conditions option in proxyman)

Another way to make the flicker more noticeable seems to be to add other packages that do some work during app init (eg react-native-unistyles).

@brentvatne Is there anything I can do to help debug/fix this?

Additional info on tests I made:

• This whole flickering happens before any of the app's JS code runs
• Upgrading to RN 0.75 according to the official expo guide doesn't solve the issue
• In a debug build, where I see the issue when I have expo-dev-client some other native deps, the screen seems to become black approximately at the time the log "Running application main ..." appears, and until after customizeRootView is called