Surface Profile Skin shading has some unexpected stripe rendering issues

UE - Graphics Features - Apr 3, 2018

So it looks like the artifact is definitely related to whether sss checkboard is enabled, but I can't reproduce it if enabling checkboard right after open the map, I mean it has to be reproduced aft ...

Incorrect Lumen Scene direct lighting when objects behind masked landscape

UE - Rendering - Graphics Features - Lumen - Oct 5, 2025

When objects are placed behind or beneath a masked landscape and r.Lumen.HardwareRayTracing.SurfaceCacheAlphaMasking is enabled, the direct light evaluation is incorrect. There are two workarounds, ...

Non-determinism in StaticMeshComponent::BodyInstance when cooking LevelInstances

UE - Simulation - Core - May 21, 2026

A licensee reported that serialization of LevelSequence with StaticMeshActor with default collision for which mesh has NoCollision profile is not deterministic. The issue seems to be in the fact tha ...

Crash when saving a Data Table that is referencing itself in a Data Table Row Handle

Tools - Feb 23, 2017

Crash when saving a Data Table that is referencing itself in a Data Table Row Handle. Reopening the project also causes a crash. *Regression: Yes This was fixed and working in 4.13-3037605 This i ...

Simulated physics bodies not working properly with BP Move Component To node

UE - Simulation - Physics - Jun 5, 2015

This issue may reference [Link Removed] which was recently fixed with 4.9 CL-2553675. When using the MoveComponentTo node physics do not work properly compared to other methods to move a component ...

BulkData Async loading remains in memory

UE - Foundation - Core - Oct 26, 2016

Gil's new loading path may already walk away from this issue. But here's some thing I tested locally if we want to fix this. A simple way to fix is to simply add BulkDataAsync.Deallocate(); ResetA ...

[CrashReport] UE4Editor_UMG!UWidget::GetParent() [widget.cpp:610]

UE - Editor - UI Systems - Oct 19, 2017

This is a trending crash coming out of the 4.18 previews and 4.18.0. Users have not provided any descriptions of their actions when the crash occurred. Source Context 597 void UWidget::SetA ...

VC Runtime not in UnrealLightmass temp directory; causing lightmass build errors

UE - Foundation - Cpp Tools - UnrealBuildTool - Oct 14, 2015

A Redistribute file for VS 2015 is needed to build lightmass, but this is not currently included with the engine. If a user does not have VS 2015 installed, lightmass will fail with this error: Un ...

Pasted material function nodes lose their connections

UE - Rendering - Architecture - Materials - Dec 3, 2019

The fix for [Link Removed] caused a regression where links to material nodes no longer carry over when a group of nodes is copied and pasted ~ User submitted Image and repro steps appended. I conf ...

Different instanced materials are seen as the same material due to GUID

UE - Graphics Features - Jun 3, 2021

See licensee description of the issue: The problem appears when I have two instanced materials with the same number of parameters. I've noticed that ShaderMapId has MaterialLayersParameterIDs where ...