Game screen out of desktop screen after quiting FULLSCREEN mode

Development Programming & Scripting AI
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3

Thank you for repeat me.I am sorry for my description.
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1,Your game starts out in full screen, but when you uncheck the box part of the game window is cut off from the screen, is that correct?

Yes, the game window 's top part is cut off from the screen.

2,What settings are changing?

I set the full screen mode in “DefaultGameUserSetting.ini”

[/Script/StormUnited.ShooterGameUserSettings]
ResolutionSizeX=2560
ResolutionSizeY=1440
LastUserConfirmedResolutionSizeX=2560
LastUserConfirmedResolutionSizeY=1440
WindowPosX=-1
WindowPosY=-1
bUseDesktopResolutionForFullscreen=False
FullscreenMode=0
LastConfirmedFullscreenMode=0

and I set the changing in “DefaultGameUserSettings.ini”

[/Script/UnrealEd.LevelEditorPlaySettings]
StandaloneWindowWidth=2560
StandaloneWindowHeight=1440

3, where when you check/uncheck the Full Screen box in game?

I check/uncheck Full screen box like following code

  //Get the CurrentResolution 
    Scalability::FQualityLevels q = UserSettings->ScalabilityQuality;
    
    FIntPoint resolotionPoint = UserSettings->GetScreenResolution();
    
    FString CurrentResolution = FString::Printf(TEXT("%dx%d"), LocalPlayer->ViewportClient->Viewport->GetSizeXY().X, 
    LocalPlayer->ViewportClient->Viewport->GetSizeXY().Y);
    
    //Get changing FullscreenModel
    FString FullscreenModelStr;
    if (Fullscreen.Equals(TEXT("1")))
    {
    	FullscreenModelStr = TEXT("f");
    }
    else
    {
    	FullscreenModelStr = TEXT("w");
    }
    
    //Set full screen or out of fullscreen
    FString CM = TEXT("r.SetRes ") + CurrentResolution + FullscreenModelStr;
    Viewport->ConsoleCommand(CM);

4,if you change the resolution after unchecking the box (exiting full screen) are you able to see the entire game window?

I tried to change resolution 480x320 it still cut off from the screen.