Blender FBXs import wrong number of bones which causes issues with Apex Cloth files

Tools - Jan 6, 2016

First of all, I'm not sure this is an issue with UE4, but I'm not familiar with Blender to rule this out. A user has reported an issue when importing a Rigged mesh from Blender it will add an addi ...

Crash when spawning destructible objects in 2 player PIE

UE - Simulation - Physics - Destruction - Aug 31, 2016

Crash Reporter link: [Link Removed] With Source Context: [Link Removed] ...

Fix log spam when using a vive wireless adpater

UE - Platform - XR - Dec 19, 2018

We need to handle TrackedDeviceClass_DisplayRedirect as a valid device in SteamVRController.cpp ...

Fix function forwarding in demo drivers in instant replays

UE - Networking - Jul 13, 2020

Demo drivers that are actively playing back a replay while still connected to another server as a client (via game net driver) will generate warnings due to the function forwarding code (UNetDriver: ...

Breaking level instances does not adequately fix up actor references

UE - World Creation - Worldbuilding Tools - Level Instances - Aug 29, 2022

Details in link. ...

Editor will crash on attempt to load a previously-saved Blueprint asset with a serialized default subobject containing a serialized static array of two or more nested subobject instances.

A crash will result if a Blueprint class that's based on a native C++ class containing two or more nested, explicitly-instanced subobjects referenced by a fixed-size object array property are serial ...

Screenspace Denoiser creates artifacts for Ray Traced Shadows

UE - Rendering - Graphics Features - Ray Tracing - Nov 13, 2023

Screen space denoiser creates two types of artifacts: artifacts around boundary for general lighting The artifact is there before 5.2 but since the ray traced shadow denoiser denoises on the sqr() s ...

UKismetArrayLibrary::GenericArray_Shuffle is weighted to return some results more than others

UE - Gameplay - Aug 15, 2017

The implementation of UKismetArrayLibrary::GenericArray_Shuffle() will generate certain array shuffle results more often (up to three times as much) than others, rather than having a roughly equal c ...

StableSpringsSystem has lots of warnings

UE - Simulation - Visual - Apr 6, 2026

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

Cook Warning "Saving FText which has been initialized from FString" when a user-defined BP structure contains a native C++ struct with an FText

UE - Framework - Blueprint - Sep 23, 2025

Consider a C++ struct containing an FText. Now consider a used-defined BP structure containing that C++ struct. When cooking an asset that references such a user-defined BP structure, the following ...