VRS Cvar Crash during CollectPSOInitializers when CVarEnableVRS.GetValueOnRenderThread() causes Ensure failure

UE - Rendering - RHI - Aug 21, 2026

We are running into an ensure that is triggered when CVarEnableVRS.GetValueOnRenderThread() is called on the game thread from FVariableRateShadingImageManager::IsAttachmentVRSEnabled. This happens ...

Render target size mistmatch in ShaderDrawDebug

UE - Graphics Features - Jun 9, 2020

We found a d3d debug validation assert in RDG_EVENT_NAME("ShaderDrawDebug"), with the full DLSS integration. It however also reproduces in  (4.25.1-release, dev-rendering and the plugin branch with ...

AddComponent node fails to be scheduled after adding an "expose on spawn" variable to an ActorComponent-based Blueprint Class.

UE - Gameplay - Blueprint - Nov 13, 2015

If an existing AddComponent node is placed in an Actor Blueprint's Event Graph for a custom ActorComponent-based Blueprint Class, the node will fail to be scheduled after adding a variable marked "E ...

Wrong density calculation in UBodySetup::CalculateMass

UE - Runtime - Simulation - Sep 29, 2025

Wrong density calculation in UBodySetup::CalculateMass. The licensee has provided the following analysis and suggested fix: In UBodySetup::CalculateMass, the following code is present: // physical ...

Unwanted black boundaries are displayed in a vertical split-screen with 3 players.

UE - Gameplay - Dec 2, 2019

Floating point error from UGameViewportClient::SplitscreenInfo causes this issue. FMath::TruncToInt( 3240 /*ViewportSize*/ * 0.333f/*Ratio in SplitScreenInfo*/ ) = 1079 I suggested a following t ...

SimpleStreamableAssetManager: Memory Bloat/Leak in AssetIndexToBounds4Index

UE - World Creation - Worldbuilding Tools - Feb 3, 2026

Overview: A report has been received regarding a memory leak that eventually leads to OOM crashes when s.StreamableAssets.UseSimpleStreamableAssetManager=1 is enabled. In projects that utilize this ...

Editor Crashes When Using Set Replicates in the Construction Script

UE - Networking - Mar 1, 2016

When spawning an actor using the Spawn Actor From Class node that has a Set Replicates node in the construction script, the editor crashes upon attempting to run a dedicated server with 2 players. ...

5.5 Static Mesh Import Pipeline Regression

UE - Editor - Content Pipeline - Import and Export - Apr 25, 2025

This question was created in reference to: [Link Removed] This post references the first post because this problem was not discovered till now. I think it was masked because the issue appears to be ...

Motion Warping component disappears on Editor restart or when swapping engine versions.

UE - MVF Character - Animation - Nov 19, 2024

Motion Warping component is disappearing on Editor restart or when swapping engine versions. When this occurs, the BP has the following Compiler Results messages: Component class is not set for'Mot ...

Ongoing D3D 'HUNG' crash in FD3D11DynamicRHI::GetQueryData

UE - Graphics Features - Jan 18, 2017

This is a new ticket for the D3D 'HUNG' crash originally reported in [Link Removed]. Some fixes were introduced in 4.14.2 that decreased the occurrences of this crash, but other cases are still ongo ...