Detaching a component may not be replicated to clients

UE - Networking - Jan 13, 2026

Because 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, 2026

When 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, 2026

The 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, 2026

If 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 ...

"Scale for <ComponentName> has a component set to zero, which will result in a bad body instance" warning spam when moving actor instance even with Collision Profile overriden to "NoCollision"

UE - Runtime - Simulation - Jan 12, 2026

When a StaticMeshComponent has a scale component of zero in WorldSpace (after accumulating with the hierarchy from the root to it), function UPrimitiveComponent::OnCreatePhysicsState() logs the warn ...

Not possible to force the Skeleton attribute to None on a default asset pipeline preset

UE - Editor - Content Pipeline - Import and Export - Jan 9, 2026

I guess that when the default value of the pipeline is None, the editor will silently pick the skeleton that is in the same folder of where you are importing. If the UI is active you can then force ...

Control Rig compile issue - Re-Entry of Instructions

UE - Anim - Rigging - Control Rig - Jan 8, 2026

Compiling a specific graph construction generates a compile error and blocks the execution of the graph. Sync to AnimSandbox CL 49645845 See attached picture and attached Control Rrig asset ...

CommonListView EntryWidgetClass allows invalid assignment via “Use Selected Asset From Content Browser”

UE - Editor - UI Systems - Jan 6, 2026

CommonListView requires its EntryWidgetClass to implement UserObjectListEntry. This requirement is correctly enforced by the Entry Widget Class dropdown, which filters out widgets that only implemen ...

Changing bIsSpatiallyLoaded can cause an Actor to be duplicated during Play-In-Editor

UE - World Creation - Worldbuilding Tools - World Partition - Dec 18, 2025

Changing bIsSpatiallyLoaded can cause an Actor to be duplicated during Play-In-Editor. As described in the steps to reproduce, if we keep swapping bIsSpatiallyLoaded state and save a Streaming Level ...

Paper2D: Editor hangs when assigning Sprite Atlas Group to Sprite

UE - Gameplay - Paper2D - Dec 16, 2025

In UE 5.3 and later, assigning a Sprite Atlas Group to a UPaperSprite asset can cause the editor to hang and eventually crash. This behavior has been reproduced in 5.3, 5.6, and a recent UE5-main so ...