Nvidia DLSS plugin causing crash in PIE

UE - Rendering - Features - Feb 10, 2023

The editor is crashing with the 5.1 Nvidia DLSS plugin enabled after performing PIE. This issue is occurring in Binary //UE5/Release-5.1 at CL 23901901 This issue is NOT occurring in Binary //UE5/ ...

Decals custom depth/stencil side effect from Lumen

UE - Rendering - Features - Oct 15, 2024

The order of passes related to Decal rendering (without the DBuffer) and CustomDepth is changed by the CVar "r.Lumen.AsyncCompute", even when Lumen is not enabled. This causes Decal Materials that ...

5.4, FRHIMemoryPool leaks memory

UE - Rendering - RHI - Feb 12, 2025

FRHIMemoryPool will leak data when it is destroyed. "FRHIMemoryPool::Init()" will create "FRHIMemoryPool::DesiredAllocationPoolSize" new "FRHIPoolAllocationData" objects, stored in "FRHIMemoryPool: ...

Level Instance Property Override: Actor::Tags overridden pre-CS but clobbered by RerunConstructionScripts with no post-CS re-apply

UE - World Creation - Worldbuilding Tools - May 4, 2026

Summary When using the Level Instance Property Override system, overrides applied to `AActor::Tags` are silently lost for Blueprint actors whose Construction Script assigns or appends to `Tags`. The ...

[CrashReport][Assert] UnrealEditor-RHI!FRHIResource::MarkForDelete() [Engine/Source/Runtime/RHI/Private/RHIResources.cpp:49]

UE - Rendering - Architecture - Materials - Dec 18, 2024

One of the users described this issue as below. "At seemingly random times while working in the material graph, some action will cause a hitch or freeze, and quickly after the engine will crash, an ...

Volumetric clouds are jagged along mesh edges when Fog Height Falloff is 0

UE - Rendering - Jul 27, 2026

Volumetric clouds are composited against opaque mesh silhouettes at a reduced resolution. A blocky and jagged edge appears along the silhouette. The fog brightness of the clouds also changes abruptl ...

Crash when saving after resetting Instanced array element via Property Matrix on placed actors

UE - Editor - Nov 21, 2025

When an Actor Component contains an Instanced UObject array marked EditDefaultsOnly, adding a new element to the Blueprint defaults correctly updates the Blueprint and its own Property Matrix. Howev ...

[CrashReport] Crash on FMaterialEditor::OnCanPromoteToParameter()

UE - Rendering - Architecture - Materials - Jun 22, 2017

This is a common crash in the 4.16 release (affecting Windows and Mac). A log file is attached. Users have not provided descriptions so additional information is not currently available. Windows C ...

Crash in FUniformExpressionSet::FillUniformBuffer trying access deleted UTextureCollection

UE - Rendering - Architecture - May 30, 2025

Crash in FUniformExpressionSet::FillUniformBuffer trying access deleted UTextureCollection (Experimental in 5.6). The licensee describes their crash, their analysis, and a proposed fix: This crash ...

Having a project for iOS set to only allow Landscape Right with show incorrectly on an iOS device

UE - Platform - Mobile - Jan 23, 2015

When you are packaging and deploying your project to an iOS device, If Supports Landscape Right orientation is the only Orientation checked, It will show incorrectly on the iOS device. Tested on an ...