I am very sorry for this problem using Google Translate.
The transparent status bar I set up with the following code has always worked well, but the following problems occur on Android 11.
B4X:
Dim jo As JavaObject
Dim window As JavaObject = jo.InitializeContext.RunMethod("getWindow", Null)
If phone.SdkVersion >= 21 Then
window.RunMethod("addFlags", Array(0x00000200))
window.RunMethod("clearFlags", Array(0x04000000))
Else
window.RunMethod("addFlags", Array(0x04000000))
End If