Android splash screen followed by gray wave transition into Godot splash screen

[sabslikesobs]

Tested versions

4.3.stable.official on Windows; Godot app 4.3 on Android
Only one Android phone tested, though.

System information

Windows 10 - Godot 4.3; Android Pixel 7a, all launchers

Issue description

Somewhat related to #92965, when a Godot-built APK launches, the android splash screen always plays a swipe cut transition from the top of the screen into the Godot game splash screen. The swipe cut resembles a gray wave. On my app, I discovered this because I wanted to launch into a pure white screen that matches my game's start screen. In my case:

1. I updated AndroidManifest.xml to make the windowSplashScreenBackground white
2. I set my game to start at a white screen
3. I set Godot's splash screen to just the color white

So I expected the app to launch all white, and then the first time I'd see any change was after my game had started. However, there's a very ugly gray, cut-off transition after the white splash screen from Android's launcher, which makes my cool app feel crappy and lame.

You can see this in the Godot 4.3 app as well, when the app launches, which should show that it probably affects all Godot-built Android apps.

Steps to reproduce

1. Open the official Godot 4.3 app
2. Observe the brief swooshing wave color
3. Close the app from Recent Apps to force a cold relaunch

Minimal reproduction project (MRP)

I don't have an MRP. Look at the official Godot app.

[orah29]

Hello,
Could you tell me how you update AndroidManifest.xml to make the windowSplashScreenBackground white ?
Thanks, Ronan