Pose watches don't display correctly with compatible skeletons

UE - Anim - Runtime - Anim Blueprints - Aug 19, 2022

"Hello, we've found a quirk with ABP's pose watch and compatible skeletons. Same setup as above. We have skeleton A as the base and skeleton B as a compatible skeleton. They both share similar hiera ...

Iris - large fast arrays serialize multiple elements when only one is dirtied

UE - Networking - Iris - Apr 8, 2025

This seems to be a result of how the changemask is handled for fast arrays. Because the changemask is a fixed set of bits (defined by IrisFastArrayChangeMaskBits), a single bit can represent multipl ...

USkinnedMeshComponent::FindClosestBone does not respect bRequirePhysicsAsset parameter

OLD - Anim - Mar 20, 2017

A licensee has reported that the USkinnedMeshComponent::FindClosestBone function does not respect the bRequiresPhysicsAsset parameter, resulting in the bone returning bones that are not part of the ...

Integer Blueprint variables reset the Bitmask Enum setting when the Editor closes

UE - Framework - Blueprint - Feb 28, 2019

User created Bitmask flag Enumerators are not correctly stored and retrieved from Blueprint Integer variable settings. When the Editor is restarted the value of the Integer's Bitmask Enum is set to ...

Mouse Events cannot be treated as Touch on Android Apps on Chromebook

UE - Platform - Mobile - Mar 18, 2019

A licensee reported an issue where mouse events are not able to be used as touch events on Android apps. This was specifically reported on and tested on Chromebooks. After working with Chris Babcock ...

Streaming levels loses static meshes coordinates and mesh references

UE - Gameplay - May 28, 2019

Streaming levels loses static meshes coordinates and mesh references when a Blueprint within the sub-levels are changed and they aren't toggled visible in the Persistent Level when it is being built ...

Unable to input with IME in widget component.

UE - Editor - UI Systems - Feb 12, 2020

Unable to input IME text in widget component, but able to input IME text in textbox like UMG designer.  It works fine until 4.21, however it wasn't able to work after 4.22. Workaround: void FSla ...

Deprecated components can still be added via the Add Component button

UE - Gameplay - Blueprint Editor - Oct 19, 2021

The UDN has a possible fix for this issue in the Component Type Registry You can use the following as a test C++ class: #pragma once #include "CoreMinimal.h" #include "Components/ActorComp ...

UInstancedStaticMeshComponentRemoveInstances crashes if called with an empty array

This looks like it can be fixed with an early-out when the passed array of indices is empty. Log:[2024.01.03-16.38.36:091][291]LogOutputDevice: Warning: Script Stack (1 frames) : /Game/BP_Crashy.B ...

Calling GetMaterial during compile on load can cause the material shader to fail to compile

UE - Rendering Architecture - Materials - Oct 4, 2024

Calling UStaticMeshComponent::GetMaterial() during a Blueprint compile on load can cause the Material shader to fail to compile because GetMaterial will trigger a PostLoad call on that Material and ...