Viewport related crash

Hi…
I’m experiencing a crash issue like many other have since 4.13 if i read correct.
Everytime i minimize/move the engine window. The engine crashes.
Notice!! I’m using a SDK version og 4.21. But still it should not matter because many have experienced the same in standalone engine versions.

What is causing this?

Fatal error: [File:C:\P4\SQ-A15\UnrealEngine\Engine\Source\Runtime\Windows\D3D11RHI\Private\D3D11Util.cpp] 
[Line: 363] SwapChain->ResizeBuffers(1, SizeX, SizeY, RenderTargetFormat, DXGI_SWAP_CHAIN_FLAG_ALLOW_MODE_SWITCH) failed at C:\P4\SQ-A15\UnrealEngine\Engine\Source\Runtime\Windows\D3D11RHI\Private\D3D11Viewport.cpp:257 with error DXGI_ERROR_INVALID_CALL, Size=696x256 Format=DXGI_FORMAT_R10G10B10A2_UNORM(0x00000018) 
0x00007ffced78a839 KERNELBASE.dll!UnknownFunction [] 
0x00007ffcc0268ada UE4Editor-Core.dll!UnknownFunction [] 
0x00007ffcc004bdf7 UE4Editor-Core.dll!UnknownFunction [] 
0x00007ffcbff84397 UE4Editor-Core.dll!UnknownFunction [] 
0x00007ffc86fafdaf UE4Editor-D3D11RHI.dll!UnknownFunction [] 
0x00007ffc86fa82d2 UE4Editor-D3D11RHI.dll!UnknownFunction [] 
0x00007ffc86f9f381 UE4Editor-D3D11RHI.dll!UnknownFunction [] 
0x00007ffc86d09067 UE4Editor-SlateRHIRenderer.dll!UnknownFunction [] 
0x00007ffc86d20368 UE4Editor-SlateRHIRenderer.dll!UnknownFunction [] 
0x00007ffca62ab1b0 UE4Editor-Slate.dll!UnknownFunction [] 
0x00007ffca6278e62 UE4Editor-Slate.dll!UnknownFunction [] 
0x00007ffca62d5b25 UE4Editor-Slate.dll!UnknownFunction [] 
0x00007ffca62d4aa3 UE4Editor-Slate.dll!UnknownFunction [] 
0x00007ff614366fb9 UE4Editor.exe!UnknownFunction [] 
0x00007ff614374ddc UE4Editor.exe!UnknownFunction [] 
0x00007ff614374e5a UE4Editor.exe!UnknownFunction [] 
0x00007ff614383b6a UE4Editor.exe!UnknownFunction [] 
0x00007ff614385812 UE4Editor.exe!UnknownFunction [] 
0x00007ffcee697bd4 KERNEL32.DLL!UnknownFunction [] 
0x00007ffceff4cee1 ntdll.dll!UnknownFunction []