Unreal Engine Issues
Unreal Engine Issues
Editor ensure in USceneComponent::OnComponentDestroyed during Blueprint compilation GC
UE - Framework - Components - Jan 15, 2026An editor-only ensure can trigger during BP compilation when garbage collection cleans up transient components created as part of component replacement. During recompilation, old component instances ...
'Hide Unconnected Pins' Button in the Blueprint Node Details Panel Disconnects SubPins with Connections
UE - Framework - Blueprint - Jan 14, 2026Given a get node with a struct output, if "Split Struct Pin" is used on the struct and one of that struct's outputs are connected to another node, it does not count as a used pin when the base get n ...
Constraint Binding ID is broken on attach track when subsequence asset is moved.
UE - Anim - Sequencer - Jan 14, 2026Moving a level sequence asset that contains actors that are being referenced as a subsequence in an attach track causes the references to drop, even though the subsequence reference is correctly upd ...
Curve Retargeting does not work with SourcePose retarget mode
UE - Anim - Rigging - Retargeting - Jan 14, 2026Currently we build what source curves we are going to remap is done inside of: FIKRetargetCurveRemapOp::AnimGraphPreUpdateMainThread But in our ikretarget processor code we skip calling that functi ...
Detaching a component may not be replicated to clients
UE - Networking - Jan 13, 2026Because the archetype for scene/static mesh components has a null value for AttachParent, there are some situations where changes to a replicated component's AttachParent are not replicated to clien ...
Detaching a component with "KeepRelative" location rule can result in incorrect location on client
UE - Networking - Jan 13, 2026When receiving a replicated detachment, USceneComponent::PostRepNotifies will call DetachFromComponent with the KeepWorldTransform detachment rule. If the component is detached on the server with th ...
bWeldSimulatedBodies not replicated with attachment
UE - Runtime - Simulation - Jan 13, 2026The bWeldSimulatedBodies attachment parameter is not replicated to clients, both in USceneComponent's attachment replication handling and in AActor's FRepAttachment struct. If AttachToComponent is c ...
USceneComponent::AttachToComponent may not be called on client depending on replication order
UE - Networking - Jan 13, 2026If the component being attached is received first, OnRep_AttachParent will set bNetUpdateAttachment to true, so USceneComponent::PostRepNotifies will call AttachToComponent. If the attach parent is ...
HISM flickering when any character is visible
UE - Rendering - Architecture - RHI - Jan 12, 2026On an NVIDIA GPU, Instanced Static Meshes can flicker when a Groom card or mesh LOD is visible. This appears related to an issue rendering the ISM into the Scene Depth. At the end of the Prepass, t ...
Light Function Materials containing a Texture Sample and Rotator nodes will fail RHI Validation
UE - Rendering - Architecture - RHI - Jan 12, 2026Using a Light Function Material that contains a Texture Sample and Rotator nodes will cause RHI Validation to fail with the following error: LogOutputDevice: Error: Ensure condition failed: Bindings ...