The app does not start up with a dark screen

We received a report from a user about an app that is being released that the app does not start up with a dark screen.

This app has been confirmed to work properly.



The user ’s device



iPad mini2

iOS 12.1.4



is.

I received a report that other apps are working without problems, so it does n’t seem to be a malfunction of the device.



I want to know when this phenomenon occurs and how to deal with it.



Development

Xcode 10.1 (10B61)

macOS High Sierra (version 10.13.6)



is.

FirebaseSDK is implemented in the app.



Thank you.