Trying to chord two buttons already mapped to actions to fire a third action when both are actuated fails.

UE - Gameplay - Input - Apr 14, 2022

We're aiming to set up LT - action 1, RT - action 2, LT + RT - action 3 here. I don't think this is supported via chording at present. You'd need to handle it manually (probably via adding/removing ...

Emissive material lighting falloff regression in GPU Lightmass

UE - Graphics Features - Sep 12, 2023

Forum user noted that emissive lighting being built with GPU Lightmass is in fact being built, just not around the mesh, but in a larger radius and with reduced strength compared to 5.1.1. They foun ...

[CrashReport] UE4Editor_Engine!UMaterialExpression::GetOutputType() [materialexpressions.cpp:859]

UE - Rendering Architecture - Materials - Nov 21, 2017

This is an infrequent crash in the 4.18 release. Users have not provided any descriptions of their actions when the crash occurred. Source Context 849 uint32 UMaterialExpression::GetOutputT ...

Unknown force is applied to the cloth when changing the skeletal mesh LoD with cloth.

UE - Simulation - Physics - Character - Jul 11, 2019

There are 3 issuesEach particles don't restore its previous position. Which is for calculating velocity by verlet iteration.The previous transform is cleared by current transform. It provides zero v ...

[CrashReport] UE4Editor_Engine!UGameViewportClient::Draw() [gameviewportclient.cpp:1170]

UE - Graphics Features - Apr 4, 2017

Was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Access violation - code c0000005 (first/seco ...

Rendering of a Text Widget with Outline does not track LayerId correctly

UE - Editor - UI Systems - May 27, 2025

Text widget with Outline uses 2 LayerId levels to draw the outline and the text glyphs. This can be seen in function FSlateElementBatcher::AddShapedTextElement(), where lambda BuildFontGeometry() is ...

Fracture Mode > "Remove-On-Break" setting: Cluster Crumbling causes flickering

UE - Simulation - Physics - Destruction - May 10, 2025

Fracture Mode > "Remove-On-Break" setting: Cluster Crumbling causes flickering. Once the Remove-On-Break Cluster Crumbling effect is activated, there is a small delay between the disappearance of th ...

[CrashReport] UE4Editor_Engine!operator new<FBatchedLine,FDefaultAllocator>() [array.h:2812]

OLD - Anim - Jun 2, 2016

Error message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 804] Array index out of bounds: 175 from an array of size 171 Source Context: 2797 2798 temp ...

FBX animations generated under fractional framerates fail to import

UE - Anim - Runtime - Aug 24, 2022

We now have the following error that is generated in FFbxImporter::ValidateAnimStackif (!FMath::IsNearlyZero(SubFrame, KINDA_SMALL_NUMBER) && !FMath::IsNearlyEqual(SubFrame, 1.0f, KINDA_SMALL_NUMBER ...

Niagara color picker user parameter preview no longer updates until confirmation

UE - Niagara - Apr 18, 2025

Starting with UE 5.4, the Color Picker Tool no longer updates preview values in real time for certain editor windows like Niagara when working with User Parameters. This behavior is a regression fr ...