A crash happens with a combination of Event Receive Tick AI and a pawn losing possession

UE - AI - May 18, 2022

User reports this is a regression because it worked in 4.27, but they converted to 5.0.1 and now it causes a crash. However, I'm unable to verify this at this time. A crash happens with a combinati ...

Crash while using Geometry Scripting to add an Array of Vector 2D data to 'Append Buffers to Mesh' node UV0 input pin

UE - Graphics Tools - Modeling Tools - Jun 13, 2022

Geometry Scripting plugin isn't available for 4.27.2, and the behavior is the same 5.0.1. Crash while using Geometry Scripting to add an Array of Vector 2D data to 'Append Buffers to Mesh' node UV0 ...

Retainer Box does not propagate Visibility settings to children

UE - Editor - UI Systems - UMG - Aug 22, 2022

This is not a regression. Tested in //UE4/Release-4.27 CL18319896 Retainer Box does not propagate Visibility settings to children. Setting Canvas visibility to 'Not Hit-Testable (Self & All Childre ...

BlackboardComponent observer can be called for the wrong key

UE - AI - BehaviorTree - Feb 7, 2023

We need to, at least, prevent this by clearing observers when running a new BT using a different blackboard. Must also think that this might affect licensees relying on the current behavior (might h ...

TranslucentVolumeAmbient is darkened in InjectTranslucencyLightingVolume pass when using VSMs with r.Shadow.Virtual.ForceOnlyVirtualShadowMaps is Off

UE - Graphics Features - Shadows - Nov 18, 2024

CSM targets are still created and affect the InjectTranslucencyLightingVolume pass when moving in a project that only uses VSM causing over brightening of fog planes and other translucent meshes. r ...

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 ...

Popping Ribbon UVs

UE - Niagara - Mar 10, 2025

Please see the Additional Link for related UDN information. The UV popping described can be subtle, depending on settings; it's affected by spawn rate and GPU vs CPU. The popping shown in the gif t ...

SSR Experimental Denoiser crashes when enabled using Vulkan

UE - Graphics Features - Apr 27, 2020

Enabled the SSR Experimental Denoiser using Vulkan causes the Engine to crash. This crash does not happen with DX11 or DX12. This happens on Linux and Windows (-vulkan). This was reported and teste ...

Editor primitives render incorrectly in stereoscopic with instanced stereo

UE - Platform - XR - Aug 17, 2016

Trigger box icons move around when oculus head movement is used. Found in //UE4/Release-Staging-4.13 @ 3090357 QA-Promotion map Edit: 08-22: This affects volumes as well as their editor icons, upd ...

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 ...