Crash during garbage collection when container UPROPERTIES specify raw interface pointer element types without TScriptInterface wrapper

UE - Foundation - Cpp Tools - UnrealHeaderTool - Oct 1, 2024

When a UPROPERTY() TMap or TArray has raw interface pointers as element type, the garbage collector tries to handle them and crashes. For raw interface pointers without a container, UHT generates a ...

Foliage HLODs don't respect "Disallow Nanite"

UE - World Creation - Worldbuilding Tools - HLOD - Jan 15, 2025

We have a level with foliage meshes that has been placed via the foliage system. We want to place these into HLOD Layers so that we can disable nanite, and thus enabling the imposter LODs at a dista ...

Landscape Layer Blending Painting Issue

UE - Graphics Tools - Terrain - Sep 10, 2025

There are two issues when painting landscape layers.Paint: When painting between different layers, square-shaped artifacts or splotches appear.Fill Layer: The blended weights of other layers aren't ...

Artifacts appear on translucent particle systems during camera motion blur

UE - Rendering - Architecture - Jul 23, 2025

Translucent particle systems exhibit visual artifacts when the camera moves, even though motion vectors are disabled for the particle emitters. While switching the Translucency Pass to "After Motio ...

VulkanStagingBuffers stat continually to grows.

UE - Platform - Mobile - Oct 24, 2025

On Android phones, VulkanStagingBuffers continually grows when the scene is static. From looking at FStagingManager, it appears the VulkanStagingBuffers atat is only updated on buffer acquisition, ...

SetBlendState has HDR UI override baked in

UE - Rendering - Architecture - Mar 20, 2026

SetBlendState() is called from non-UI code but has HDR UI overrides baked in. The UI specific code should be moved to the UI code that calls SetBlendState() - likely in FCanvas, or the function sho ...

Trigger Volume Blocks First-Person Template Projectile

UE - Simulation - Physics - Nov 2, 2015

When playing in editor, if you fire your weapon at a trigger volume, the projectiles will bounce off of the volume, regardless of the fact that the collision is set to Query Only. This collision als ...

Importing multiple SpeedTree assets that use the same texture will not assign correctly

UE - Graphics Features - Sep 25, 2015

When importing multiple SpeedTree assets that use the same material will cause one to import blank (black) materials and assigned. This happens when importing into the same folder, however, if impor ...

Opening the editor with -opengl4 causes the viewport camera to go black

UE - Platform - Linux - Apr 14, 2015

If the -opengl4 command is used while launching the editor it will cause the viewport to go black if something in the level is selected or while using RMB to look around the level. ...

Enumeration selections within structs do not properly populate within data tables

Tools - Dec 1, 2015

The first selection of Enums within a struct array do not properly pouplate the table within a datatable (see attached image datatableEnum1). Any other selection populates the datatable, however it ...