OnClicked event of UMG button fires once in twice if virtual joystick is receiving input.

UE - Editor - UI Systems - Oct 14, 2015

OnClicked event of UMG button fires once in twice if virtual joystick is receiving input. Both Andorid and iOS devices are affected. This issue is found with 4.9 update. under 4.8 are fine. ...

Private lobbies cannot be invited to on Steam

UE - Online - May 13, 2019

The old method doesn't work with private match invites as it doesn't have the right security permissions. It's still valid for dedicated servers. It also doesn't work properly with lobbies on VR eit ...

Montage Root Motion does not work from sub anim instances

UE - Anim - Gameplay - Oct 25, 2019

Root motion from sub instances is not used when the parent instance is marked as 'Root Motion from Montages Only'. Proposed fix is to modify USkeletalMeshComponent::IsPlayingNetworkedRootMotionMo ...

ISM Component in an instanced BP does not take into account changes to NumCustomDataFloats from the BP class

UE - Graphics Features - Sep 16, 2022

PerInstanceSMCustomData is bulk serialized and doesn't get changed on the BP instance when changing NumCustomDataFloats, possibly causing out of bounds array access leading to a crash. Possible sol ...

FMaterialResource::IsDualBlendingEnabled bug

UE - Rendering Architecture - Materials - Jul 24, 2023

The user has a proposed fix for this in the case. FMaterialResource::IsDualBlendingEnabled needs the following modification that includes MaterialInstance check: bool bMaterialRequestsDualSourceBle ...

Auto Exposure Compensation Curve issue when switching from Histogram to Manual

UE - Rendering Architecture - Feb 21, 2024

When switching the Camera's Exposure Metering Mode from Histogram to Manual, there is a single-frame flash. The Licensee has a proposed code change that would fix this issue. Also found in 5.4, CL 3 ...

Performance hitch from RemoveGeometryCache flushing the render thread

UE - Editor - Content Pipeline - Alembic - Jun 12, 2025

FGeometryCacheStreamingManager::RemoveGeometryCache calls FlushRenderingCommands which shows up as a hitch when profiling. [Link Removed] Ideally the flush added in CL#23782411 to fix a rare deadl ...

Casting to a child with a self reference can cause a crash

UE - Gameplay - Blueprint - Aug 13, 2015

Casting to the child of a blueprint using the self reference (as the parent) throws a warning. Then placing a self reference anywhere in the event graph of the child by it's self will cause a crash ...

FFieldPath resolution doesn't handle redirection

UE - CoreTech - Feb 16, 2022

A licensee has found that redirectors don't apply to FFieldPath. We should integrate it with the following changes:It needs better error handling (looks like it could infinitely recurse),The change ...

VR Preview crashes when the number of players is greater than one

UE - Platform - XR - Aug 18, 2015

If the user has the number of players set to more than one, the VR preview will crash. ...