Fields with Maximum resolution are not affecting all leaves of a Geometry Collection

UE - Runtime - Deformable - Apr 25, 2025

Fields with Maximum resolution are not affecting all leaves of a Geometry Collection on 5.4 and onwards. When calling GetRelevantParticleHandles() a Maximum Resolution field does return all particl ...

Layered Blend Per Bone nodes evaluate to 0.0 weight with Blend Masks when s.AsyncLoadingThreadEnabled is active in Editor

UE - Runtime - Anim BP - Aug 11, 2026

When starting the Editor, Layered Blend Per Bone nodes using Blend Masks inside dynamically linked Anim Layers completely ignore the blend pose (evaluating to 0.0 weight for all bones). Disconnectin ...

Inconsistent Behavior in TextureLODGroups when setting NumStreamedMips=0

UE - Rendering - Architecture - Jan 8, 2026

A licensee has reported that it is not possible to disable texture streaming of a given TextureLODGroup by setting "NumStreamedMips=0" in their device profiles. Currently, using 0 results in the sam ...

Scaling actor along the Z Axis while the X and Y axis are set to 0.01 causes the Actor to stop rendering in the scene

UE - Rendering - Features - May 27, 2022

This is a regression tested in //UE5/Release-5.0 CL18319896 Scaling a Static Mesh along the Z Axis while the X and Y axes are set to 0.01 causes the Actor to stop rendering in the scene once the Z ...

Reflections of Masked Materials incorrect with Lumen HWRT and Max Refraction Bounces > 0

UE - Rendering - Features - Lumen - Dec 18, 2025

Lumen HWRT Reflections of Masked Materials are incorrect when "r.Lumen.Reflections.HardwareRayTracing.Translucent.MaxRefractionBounces" is greater than 0. The same issue occurs if the Post-Process V ...

FBX Import - Morph target normals not correctly applied when imported as LOD 0

UE - Editor - Open File Formats - FBX - Nov 27, 2025

This is a regression since 5.5 with skeletal meshes where morph target normal/tangent deformation only works when a mesh is imported as a LOD of an existing skeletal mesh, but not when imported as L ...

Foot Placement: Division by 0

UE - MVF Character - Animation - Jan 31, 2025

static FVector PointDirectionPlaneIntersection(const FVector Point, const FVector Direction, const FPlane Plane) { return Point + Direction * ((Plane.W - (Point | Plane)) / (Direction | Plane)) ...

Biquad Filter is incorrect when bandpass is 1.0

UE - Audio - Aug 20, 2024

The bandwidth on the biquad loepass filter is cutting frequencies well below 20kHz when the bandwidth is 1.0. Slack convo: [Link Removed] Visualization:[Image Removed] ...

Wrong density calculation in UBodySetup::CalculateMass

UE - Runtime - Simulation - Sep 29, 2025

Wrong density calculation in UBodySetup::CalculateMass. The licensee has provided the following analysis and suggested fix: In UBodySetup::CalculateMass, the following code is present: // physical ...

Non-Nanite meshes not being correctly cleared from all levels of VSMs on actor destruction when r.Shadow.Virtual.NonNanite.IncludeInCoarsePages=0

UE - Rendering - Features - Shadows - Jun 15, 2026

When using the r.Shadow.Virtual.NonNanite.IncludeInCoarsePages=0 to optimize VSM performance there are errors in how the VSM is invalidated when actors are destroyed with non-Nanite meshes. The curr ...