Hang and log spam when making changes to a landscape material with the landscape editor open

UE - LD & Modeling - Terrain - Landscape - Jul 25, 2016

Editor hangs if changes are made to the material which is currently assigned to a landscape while the landscape editor is open. Also spams "LogMaterial: 0.03 seconds spent updating 1 materials, 1 i ...

Planar Reflection Actor does not pivot at center when using ALT+LMB Drag in Viewport

UE - Graphics Features - Jan 31, 2020

When moving a Planar Reflection Actor's transform location to (X:5000, Y:5000, Z:0)  The Planar Reflection Actor does not pivot at center when using ALT+LMB Drag in the viewport.   Note: Moving tra ...

Division by zero in FAnimNode_StrideWarping::EvaluateSkeletalControl_AnyThread

UE - Anim - Gameplay - Sep 29, 2025

When an Actor's CustomTimeDilation is 0.0, functions FActorTickFunction::ExecuteTick() and FActorComponentTickFunction::ExecuteTickHelper() will call AActor::TickActor() and UActorComponent::TickCom ...

Nanite meshes are lit differently in Actor Colorization view modes than non-Nanite meshes

UE - Graphics Features - Nanite - Aug 28, 2024

When the Lit > Actor Coloration > Affects Navmesh or other Actor Coloration mode is used, Nanite meshes apply lighting differently than non-Nanite meshes which can make it difficult to use the Actor ...

Different Number of Frames imported from the same FBX between UE 4.8 and 4.9

OLD - Anim - Sep 14, 2015

Using the same import settings in UE4.8 and UE4.9 will result in a different number of frames of an animation being imported from the same FBX file. If you import the same fbx animation which in M ...

UInstancedStaticMeshComponentRemoveInstances crashes if called with an empty array

This looks like it can be fixed with an early-out when the passed array of indices is empty. Log:[2024.01.03-16.38.36:091][291]LogOutputDevice: Warning: Script Stack (1 frames) : /Game/BP_Crashy.B ...

Running the BuildPlugin command results in a warning that ForceCompile is not supported and an error that an item with the same key has already been added

UE - Foundation - Cpp Tools - Automation Tool - Dec 7, 2022

Repro Rate: 5/5 This issue was encountered in the 5.1.0 live launcher build of //UE5/Release-5.1 at CL 23058290 and reproduced by other users. Regression tested against the 5.0.3 live launcher bui ...

Compiling any material in UE 5.5.1 without ShaderCompiler JobCache results in a crash

UE - Rendering Architecture - Shaders - Jan 15, 2025

Compiling any material with r.ShaderCompiler.JobCache=0 causes ShaderCompileWorker to crash. Reproduction steps cause a crash during Editor startup, but this bug may affect other scenarios where mat ...

ALT-Drag a non-DBuffer Decal will Crash the Engine

UE - Graphics Features - Jun 11, 2015

When you ALT-Drag a Decal that is not using the Dbuffer settings, the Engine will crash. The issue is not reproducible in Main Promotable-CL-2581018 This is a regression. Worked in 4.7.6, broken ...

Using Blend Physics Weight causes skeletal mesh to spin at high speed

OLD - Anim - Mar 5, 2015

When Phyics Blend in the PHAT editor is set between 0 and 1, the user character will spin wildly. User has image of this affecting character in game whereas I was only able to replicate it in the PH ...