texture->UpdateResource() Crash when downloading array of assets

Hi all. I could really use some help with a bug when downloading multiple image assets from the web.

I have tried in 4.25 and 4.26 versions of Unreal with C++ and blueprint implementations.

I have an array of URLs of jpeg files online which need to be downloaded into the project at runtime.

However, there is a crash that happens on random images.

[2020.12.16-13.47.31:602][467]LogWindows: Error: Fatal error: [File:F:/UnrealSource_4_25_3/Engine/Source/Runtime/RenderCore/Private/RenderingThread.cpp] [Line: 907] 
[2020.12.16-13.47.31:603][467]LogWindows: Error: Rendering thread exception:
[2020.12.16-13.47.31:604][467]LogWindows: Error: Fatal error!
[2020.12.16-13.47.31:605][467]LogWindows: Error: 
[2020.12.16-13.47.31:608][467]LogWindows: Error: Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x0000000000000048
[2020.12.16-13.47.31:608][467]LogWindows: Error: 
[2020.12.16-13.47.31:609][467]LogWindows: Error: [Callstack] 0x00007ff9d08af917 UE4Editor-Engine.dll!UnknownFunction [F:\UnrealSource_4_25_3\Engine\Source\Runtime\Engine\Private\Texture.cpp:162]
[2020.12.16-13.47.31:609][467]LogWindows: Error: [Callstack] 0x00007ff9d08cee1d UE4Editor-Engine.dll!UnknownFunction [F:\UnrealSource_4_25_3\Engine\Source\Runtime\RenderCore\Public\RenderingThread.h:183]
[2020.12.16-13.47.31:610][467]LogWindows: Error: [Callstack] 0x00007ff9d08d2354 UE4Editor-Engine.dll!UnknownFunction [F:\UnrealSource_4_25_3\Engine\Source\Runtime\Core\Public\Async\TaskGraphInterfaces.h:886]
[2020.12.16-13.47.31:611][467]LogWindows: Error: [Callstack] 0x00007ff9d264e6c8 UE4Editor-Core.dll!UnknownFunction [F:\UnrealSource_4_25_3\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:709]
[2020.12.16-13.47.31:611][467]LogWindows: Error: [Callstack] 0x00007ff9d264eace UE4Editor-Core.dll!UnknownFunction [F:\UnrealSource_4_25_3\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:601]
[2020.12.16-13.47.31:612][467]LogWindows: Error: [Callstack] 0x00007ff9cf0daa62 UE4Editor-RenderCore.dll!RenderingThreadMain() [F:\UnrealSource_4_25_3\Engine\Source\Runtime\RenderCore\Private\RenderingThread.cpp:373]
[2020.12.16-13.47.31:613][467]LogWindows: Error: [Callstack] 0x00007ff9cf0e3134 UE4Editor-RenderCore.dll!UnknownFunction [F:\UnrealSource_4_25_3\Engine\Source\Runtime\RenderCore\Private\RenderingThread.cpp:509]
[2020.12.16-13.47.31:613][467]LogWindows: Error: [Callstack] 0x00007ff9d2ba3cfb UE4Editor-Core.dll!UnknownFunction [F:\UnrealSource_4_25_3\Engine\Source\Runtime\Core\Private\Windows\WindowsRunnableThread.cpp:86]
[2020.12.16-13.47.31:620][467]LogWindows: Error: [Callstack] 0x00007ff9d2b9c9d0 UE4Editor-Core.dll!UnknownFunction [F:\UnrealSource_4_25_3\Engine\Source\Runtime\Core\Private\Windows\WindowsRunnableThread.cpp:35]
[2020.12.16-13.47.31:625][467]LogWindows: Error: [Callstack] 0x00007ffa3f447bd4 KERNEL32.DLL!UnknownFunction []
[2020.12.16-13.47.31:626][467]LogWindows: Error: [Callstack] 0x00007ffa40d6ce51 ntdll.dll!UnknownFunction []

The crash is caused by an exception when checking IsRenderingThreadHealthy()

I have wrote my own version of the AsyncDownloadImageTask to try hunt down the issue and it happens when texture->UpdateResource() is called.

				if (UTexture2DDynamic* texture = UTexture2DDynamic::Create(imageWrapper->GetWidth(), imageWrapper->GetHeight()))
				{
					texture->SRGB = true; 
					texture->UpdateResource(); // <----------------- Crash
             // Code to create texture data on the render thread here

I have been stuck on this issue for a while now and it’s important I am able to download a collection of images from the web. Any suggestions or work arounds would be hugely appreciated.

Thank you in advance

Alex