Unreal Engine Issues
Unreal Engine Issues
"Move Selection to Current Level" can duplicate actors when cancelling
UE - World Creation - Worldbuilding Tools - Apr 17, 2026When moving an Actor that is referenced in the source level, UEditorEngine::CopySelectedActorsToClipboard will try to select the Actor for delete which will pull the \"Delete Referenced Actor\" dial ...
Deadlock during cooking or editor in URigHierarchyController::AddElement on task thread while GarbageCollection occurs on gamethread.
UE - Runtime - Animation - Apr 15, 2026In URigHiearchyController::AddElement (and other functions), arbitrary delegate code is called while holding Hierarchy->ElementsLock, through the Notify function. URigHierarchy::AddReferencedObject ...
[StateTree] Cannot use SetLinkedStateTreeOverrides if the linked asset uses the same schema with a parent context data class of the root tree.
UE - AI - StateTree - Apr 3, 2026If both assets have the same schema (StateTreeComponentSchema), but the root tree has the Context Actor class set to Character and the linked asset is using a Context Actor class of Pawn. So the sch ...
Mutable: Child parameters hidden when intermediate Object Group uses "All Options"
UE - Anim - Mutable - Mar 31, 2026FCustomizableInstanceDetails::FillChildrenMap() unconditionally registers parent-child relationships via __ParentParamName metadata without verifying the parent exists in the active parameter list. ...
Mesh Reshape node with modified geometry from another skeleton explodes mesh.
UE - Anim - Mutable - Mar 31, 2026Using the mesh reshape node with seperate meshes produces a broken mesh. An example project: Most if not all clothes will be originally made to fit the Average Male body. I'm trying to morph a tu ...
CSM Cached Shadows missing when changing FOV
UE - Rendering - Graphics Features - Shadows - Mar 30, 2026When changing the camera FOV with r.Shadows.CSMCaching enabled, the cached shadows don't appear to be used and shadows are missing. This occurs because the r.Shadow.RadiusThreshold can be low enoug ...
Issue with r.SkyAtmosphere.TransmittanceLUT.UseSmallFormat
UE - Rendering - Features - Mar 30, 2026When "r.SkyAtmosphere.TransmittanceLUT.UseSmallFormat=1", some values for the Sky Atmosphere at some directional light angles can lead to the sun disk being cut off, and taking on a chord shape. A ...
Chaos Fields: LS_MasterField continuously creates components every frame and never cleans them up
UE - Runtime - Deformable - Mar 25, 2026While active and ticking, the built-in FS_MasterField actor instance continuously creates several new components every frame, which are never cleaned up until the actor is destroyed. This can happen ...
WorldPartitionChangelistValidator incorrectly flags actors referencing the level script actor as invalid
UE - World Creation - Worldbuilding Tools - World Partition - Mar 23, 2026When validating a change list that contains an actor that references the level script in the world (e.g. it has an event bound on the level script graph) it will fail changelist validation 100% of t ...
Editor crash in HairStrandsMeshProjection.cpp when spawning actor with Groom Component bound to skeletal mesh
UE - Gameplay Features - Character - Mar 23, 2026The editor crashes with an assertion failure when placing a Blueprint actor that contains a Groom Component bound to a MetaHuman skeletal mesh. The crash occurs in AddHairStrandInitMeshSamplesPass d ...