Unreal Engine Issues
Unreal Engine Issues
Morph target is not applied on the first frame in Level Sequence
UE - Anim - Rigging - Dec 4, 2025When a skeletal mesh with morph targets spawns in the sequence, the morph is not reflected in the first frame. In the ProcessStage_SkinCache call of SkeletalMesh, MorphVertexBuffer->SectionIds is ...
Mover plugin: Crash on UFloorQueryUtils::ComputeFloorDist() and other utility functions that assume the pawn uses a UCapsuleComponent
UE - Gameplay - Player Movement - Mover - Dec 4, 2025The following functions have been found to perform unchecked casts of the pawn's "UpdatedComponent" to class UCapsuleComponent, possibly resulting in crashes:UFloorQueryUtils::ComputeFloorDist()UGro ...
Unreal Engine Fails to Launch with Vulkan SM6 RHI and RenderDoc Auto-Attach Enabled
UE - Rendering - Architecture - RHI - Dec 3, 2025When launching Unreal Engine with the Vulkan RHI, SM6 and RenderDoc Auto Attach on Startup enabled, the engine fails to initialize with the error: “A compatible Vulkan Driver is required to run the ...
PlayerCollision visualization incorrect on LandscapeSplineMesh when Nanite is enabled
UE - Graphics Features - Nanite - Dec 3, 2025From licensee: I’ve found an issue with the visualization of PlayerCollisions when using LandscapeSplineMesh with a mesh that has Nanite enabled. The Chaos collisions shown in the Chaos Visual Debu ...
Standalone Level Instance with WorldPartition world don't load in editor
UE - World Creation - Worldbuilding Tools - Level Instances - Dec 2, 2025A WorldPartition map used as a level instance that's set to standalone mode doesn't load its actors in the editor. ...
DoDeferredRender will not UpdateBound correctly when NavigationCachedBoundsUpdated
UE - AI - Navigation - Dec 2, 2025With InstancedStaticMeshComponent, after calling AddInstance, an instance that’s far away gets culled because of additional logic that was added in 5.7 to This works correctly in 5.6 and the instanc ...
Material LocalPosition node does not work correctly with Nanite Skinned meshes
UE - Graphics Features - Dec 1, 2025Nanite Skinned Meshes don't receive the correct Local Position in some shadow passes. This depends on the clipmap level, and is not related to VSM caching. Unreal Engine 5.6 shows the same issue, b ...
In 5.7, a Sequencer that contains a Spawnable ChaosCacheManager will crash the Engine on EndPlay
UE - Simulation - Physics - Nov 30, 2025In 5.7, a Sequencer that contains a Spawnable ChaosCacheManager will crash the Engine on EndPlay. The licensee has reported, and I've confirmed, that this behavior started in 5.7. I've confirmed thi ...
Blueprints can enter a corrupted state where Actors construct DefaultSubobjects using CreateOptionalDefaultSubobject, even though child classes call DoNotCreateDefaultSubobject
UE - Framework - Blueprint - Nov 28, 2025Blueprints can enter a corrupted state where Actors construct DefaultSubobjects using CreateOptionalDefaultSubobject, even though child classes call DoNotCreateDefaultSubobject. In some situations, ...