Incorrect derivative ops detection when Add node is used with Nanite Pass Switch node in material graph

UE - Graphics Features - Mar 11, 2025

Plugging an Add node which adds a constant value into a Nanite Pass switch node results in derivative ops to be detected where there should be none (which show up as red in the No Derivative Ops deb ...

Ribbon Particle Normals are reversed from default Sprite Particles

UE - Graphics Features - Oct 13, 2015

It appears that the Vertex Normals from Ribbon Particles are opposite of what is expected via the Default Particle System given both systems share the same alignment (Facing Camera) [Image Removed] ...

Physics enabled Child Actor components that spawn with with a delay, always spawns at world origin

UE - Gameplay - Jun 3, 2016

Physics enabled Child Actor components that spawn with with a delay, always spawns at world origin **This is a regression. It was working in 4.11.2 Could also be related to: [Link Removed] User D ...

Crash when Undo after deleting a Material Layer of a Material Instance.

UE - Rendering Architecture - Materials - Apr 2, 2025

In Unreal Engine version 5.5.4, the Editor crashes when performing Undo after deleting a Material Layer of a Material Instance ...

Trace complex for assets simulating physics does not show accurate collision

UE - Gameplay - Apr 27, 2015

When using Trace Complex in a LineTraceByChannel node does not give accurate results when object is simulating physics and scaled. The scaled root mesh in the BP will only register its collision rat ...

CppCompileWarningSettings.NonInlinedGenCppWarningLevel messages should contain Warning\Error

UE - Foundation - Cpp Tools - UnrealBuildTool - Oct 8, 2025

The messages emitted when CppCompileWarningSettings.NonInlinedGenCppWarningLevel is set to Warning\Error should contain the literal so the tools pick them up and react accordingly. From the EPS c ...

Packaging for DLC with plugin multiple times causes failure due to file path length

When the DLC is being built for a project and stored in a plugin, the result is normaly until the DLC is packaged multiple times. This leads to the file path becoming more and more nested each time. ...

Add Submix Effect Blueprint Does Not Have Any Effect

UE - Audio - Dec 11, 2020

Adding a second effect to the Submix Effect Chain on a Submix works as expected, but when trying to add a Submix Effect via Blueprint, there is no effect.  This also applies to "Add Master Submix Ef ...

A chaos vehicle that moves at very high speeds with CCD enabled on the vehicle sometimes has a collision response that is abnormal where the vehicle loses a significant amount of speed when colliding with dynamic objects configured as One Way Interaction

UE - Simulation - Gameplay - Dec 16, 2025

Context: Continuous Collision Detection (CCD) is being used on a Chaos Vehicle to avoid tunneling issues with certain surfaces as it prevents any missed collisions between fast moving particles and ...

Cumulative Patching does not work with Pak signing

UE - Foundation - Feb 20, 2024

Cumulative patching is implemented by copying the generated pak files during staging of the base and each patch to the Releases directory. When creating a patch, all of the pak files from the releas ...