Curve Debugger window is broken when viewing curves in the Anim Sequence editor

UE - Anim - Runtime - Oct 15, 2025

The curve debugger is currently broken when viewing curves on anim sequences. It seems that only metadata/skeleton curves are displayed, and those aren't updating correctly or showing their type (m ...

[Interchange] FBX - Front Facing X-Axis and Flipped Bone Orientation During Animation

UE - Editor - Content Pipeline - Import and Export - Oct 15, 2025

Actors attached to a skeleton imported through a FBX file with the Front Facing X-Axis option enabled are flipped when the skeleton is animated. ...

Intermittent Content is Missing from Cook errors for objects with Niagara packages

UE - Niagara - Oct 15, 2025

Intermittently when cooking large licensee projects, an error is reported at the end of the cook:LogCook: Error: Content is missing from cook. Source package referenced an object in target package b ...

Light Leak Issue in Modular Buildings (Lumen HZBTraversal)

UE - Graphics Features - Lumen - Oct 14, 2025

Starting in Unreal Engine 5.6, disabling "r.Lumen.ScreenProbeGather.ScreenTraces.HZBTraversal" can lead to light leaking between adjacent or overlapping meshes. Also tested on Release-5.6, CL: 4523 ...

Material Instance Platform Stats don't update when Material Layer parameters are changed

UE - Rendering Architecture - Materials - Oct 14, 2025

The instruction count appears to update properly if the whole asset editor is closed and reopened. ...

Extend Worldpartition Editor Grid Widget

UE - World Creation - Worldbuilding Tools - World Partition - Oct 14, 2025

Licensees are looking into ways of adding visualizations to the editor worldpartition grid widget. In one example case, just adding some lines to show which parts of the wp minimap belong to which s ...

Smart Link inactive by default when NavLink is a ChildActor

UE - AI - Navigation - Oct 14, 2025

When placing a NavLinkProxy in ChildActor, the link is not enabled by default. In this situation, setting SetSmartLinkEnabled to true does not establish the connection. You must first set it to fal ...

Lightmass CalculatePointShadowing regression in UE5.6

UE - Graphics Features - Oct 14, 2025

There is a regression or change in the Build Lighting process when using Lightmass in Unreal Engine 5.6:When building lighting with Lightmass calling the CalculatePointShadowing function, the result ...

Spline mesh deform breaks WPO when used with Nanite meshes

UE - Graphics Features - Nanite - Oct 13, 2025

Nanite spline meshes deforming along the world normal vector do not use the same world normal as a non-Nanite spline mesh. This results in inconsistent behavior between Nanite and non-Nanite spline ...

Ensure in FOnlineSubsystemSteam::Shutdown when using OSS Adapter

UE - Online - Oct 13, 2025

This looks to occur because of the order in which the OSS Adapter module and Steam OSS module are shut down. The OSS Adapter holds onto references to the OSS's interfaces, so when the Steam OSS modu ...