UE4 window control (maximize minimize)

After packing , Click on exe file , The default is full screen , Press down F11, Will shrink . A folder appears save Folder

A configuration file will be generated inside

[ScalabilityGroups]
sg.ResolutionQuality=100.000000
sg.ViewDistanceQuality=3
sg.AntiAliasingQuality=3
sg.ShadowQuality=3
sg.PostProcessQuality=3
sg.TextureQuality=3
sg.EffectsQuality=3
sg.FoliageQuality=3
sg.ShadingQuality=3

[/Script/Engine.GameUserSettings]
bUseVSync=False
bUseDynamicResolution=False
ResolutionSizeX=1600
ResolutionSizeY=900
LastUserConfirmedResolutionSizeX=1600
LastUserConfirmedResolutionSizeY=900
WindowPosX=-1
WindowPosY=-1
FullscreenMode=2
LastConfirmedFullscreenMode=2
PreferredFullscreenMode=1
Version=5
AudioQualityLevel=0
LastConfirmedAudioQualityLevel=0
FrameRateLimit=0.000000
DesiredScreenWidth=1280
bUseDesiredScreenHeight=False
DesiredScreenHeight=720
LastUserConfirmedDesiredScreenWidth=1280
LastUserConfirmedDesiredScreenHeight=720
LastRecommendedScreenWidth=-1.000000
LastRecommendedScreenHeight=-1.000000
LastCPUBenchmarkResult=-1.000000
LastGPUBenchmarkResult=-1.000000
LastGPUBenchmarkMultiplier=1.000000
bUseHDRDisplayOutput=False
HDRDisplayOutputNits=1000

[ShaderPipelineCache.CacheFile]
LastOpened=UDPTest

modify FullscreenMode = 0; Full screen .