When using a Blend node inside a Post Process Animation Blueprint, the editor crashes while rendering thumbnails. The crash occurs because USkeletonThumbnailRenderer attempts to draw a thumbnail with a USkeletalMeshComponent that hasn’t properly initialized its animation nodes. Specifically, FAnimNode_BlendListBase::PerBlendData is null, leading to the engine crash.
1- Open the project.
2- Open PPABP_SKEL (Post Process Animation Blueprint).
3- Compile it.
4- Close PPABP_SKEL.
5- Reopen it.
6- The editor crashes.
USkeletalMeshComponent::SetSkeletalMesh SkeletalMeshComponent.cpp:3397
FSkeletalMeshThumbnailScene::SetSkeletalMesh ThumbnailHelpers.cpp:468
USkeletonThumbnailRenderer::Draw SkeletonThumbnailRenderer.cpp:50
ThumbnailTools::RenderThumbnail ObjectTools.cpp:5516
FAssetThumbnailPool::LoadThumbnail AssetThumbnail.cpp:2247
FAssetThumbnailPool::LoadThumbnail AssetThumbnail.cpp:2289
FAssetThumbnailPool::Tick AssetThumbnail.cpp:2169
FTickableEditorObject::TickObjects TickingEditorObject.h:33
FTickableObjectBase::SimpleTickObjects Tickable.cpp:119
FTickableEditorObject::TickObjects TickableEditorObject.h:30
UEditorEngine::Tick EditorEngine.cpp:1906
UUnrealEdEngine::Tick UnrealEdEngine.cpp:530
UDwEditorEngine::Tick DwEditorEngine.cpp:84
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