StableSpringsSystem has lots of warnings

UE - Runtime - Deformable - Apr 6, 2026

System successfully compiled with 16 warnings. /Engine/Generated/NiagaraEmitterInstance.ush:2732:250: note: variable 'OutMaterialMultiplier' is declared here void SolveDistanceSpringMaterial_Emitter ...

Procedural meshes spawned at runtime cause a crash

UE - Simulation - Physics - Jan 10, 2017

When using a procedural mesh at runtime, projects fail on mobile devices. Tested on both Android Nvidia Shield and iPhone 6+. ...

When using Lighting Scenario, loading order will affect how it's applied to the instances

UE - World Creation - Worldbuilding Tools - Foliage - Mar 7, 2019

When using Lighting Scenario, loading order will affect how it's applied to the instances, resulting in corruption if content is loaded after the lighting scenario ...

Orthographic Rendering - Lumen Reflection Artefacts

UE - Rendering - Architecture - Apr 28, 2023

Mutable custom versioning issue from 5.5->5.6

UE - Anim - Mutable - Sep 19, 2025

In 5.6, a handful of new entries in `FCustomizableObjectCustomVersion` were added, including `SetDisplayNamePropertyAsPinNameOfTableNodes`. Looking back at the history, `SetDisplayNamePropertyAsPinN ...

CSM has artifacts if shadow distance less than 2000

UE - Graphics Features - Jun 12, 2019

Startup Movies Fail to Play when Audio Devices are Disabled

Tools - Feb 1, 2016

If a user launches a project in Standalone mode and has a Startup movie while the audio devices on the computer are disabled, the movie will fail to play. As soon as you re-enable an audio device, ...

Crash when changing the number of instances in a grouped sprite component at runtime

UE - Gameplay - Paper2D - Aug 4, 2016

A crash occurs when you remove a Sprite Instance within a Paper Grouped Sprite component of an Actor BP on Event Begin Play. I was able to reproduce this crash in the binary releases of 4.11.2 and ...