Scene Color node with UV input on a transparent material renders incorrectly in stereo

UE - Platform - XR - Jan 19, 2021

From Licensee: When we have Instanced Stereo enabled, all our materials that use Scene expression nodes (SceneDepth, SceneColor, etc...), render incorrectly in the right eye. It only happens to the ...

Combined Translate and Rotate Mode broken when using Local Space

UE - Editor - Dec 22, 2023

From UDN: When using the Combined Translate and Rotate Mode we run into an issue where the rotation arrow moves twice as fast as the coordinate frame. The object itself rotates correctly, but if we ...

BP - Nativization will fail at cook time if a BP class and a User-Defined Structure reference each other.

UE - Gameplay - Blueprint - Apr 20, 2017

Note: This happens with "Exclusive" nativization mode as well. This occurs because the nativized UDS 'GetDefaultValue()' method is generated into a .h file rather than a .cpp file. This creates a c ...

Variant manager crash in UPropertyValue::HasValidResolve

UE - Editor - Content Pipeline - Variants - Nov 21, 2024

in the past we have reported a lot of VM related bugs which got fixed over time. Unfortunately, I think we have another one. Right now we're using 5.0.3 binaries from the launcher. Now the pro ...

Nanite: unused VertexInterpolator node disables Opacity Mask (material renders opaque)

UE - Rendering - Architecture - Jun 8, 2026

On Nanite meshes, placing a VertexInterpolator node in a material graph without using it (unconnected, or routed through a disabled static switch) silently breaks the Opacity Mask and the material r ...

ApplicationReceivedScreenOrientationChangedNotificationDelegate does NOT work properly on Android

UE - Platform - Mobile - Aug 5, 2019

ApplicationReceivedScreenOrientationChangedNotificationDelegate supports iOS but not Android. Probably, Java_com_epicgames_ue4_GameActivity_nativeOnConfigurationChanged should be useful for fix thi ...

ensure(false) being fired in FGenericParticlePairMidPhase::FindOrCreateConstraint from key collision

UE - Simulation - Core - Jan 27, 2025

ensure(false) being fired in FGenericParticlePairMidPhase::FindOrCreateConstraint from key collision. The licensee reports one of their users reported this issue and they were able to reproduce a fe ...

Spot Light USD Export Produces Incorrect Intensity Values Based on Cone Angle and Source Radius

UE - Editor - Content Pipeline - USD - Apr 3, 2026

UPDATE: Should be fixed as of CL#52537078 (fb7af1) USD: Bake all frames of exposure animation tracks. When exporting Unreal Engine spot lights from a level to USD, lights with identical EV intensit ...

Linux: Assertion at splash screen when trying to open UE4Editor

UE - Platform - Linux - Mar 21, 2017

I ran into this while looking to verify [Link Removed] at CL 3355923. I logged the issue I was verifying the fix for last night and have not updated anything locally, so the "OpenGL 4.3 not supporte ...

Inconsistent ListView entry sizes can prevent the ListView from being scrolled to the bottom

UE - Editor - UI Systems - Slate - May 4, 2022

Since the contents of a ListView are virtualized, the ListView estimates the size of the scroll box's contents based on the on-screen elements. This can lead to some situations where DistanceFromBot ...