Issue when turnning a character into ragdoll using PhysicsControlComp with async physics

UE - Anim - Synthesis - Jul 16, 2024

When turnning a moving character into ragdoll, it freeze a bit with TickPhysicsAsync on. If we log the character's pelvis position, it seems jump backward in the first few ticks. Also, it only happ ...

Enabling ZenLoader causes editor crash when undoing Level Instance deletion

UE - CoreTech - Sep 5, 2024

Crash reported through UDN. With ZenLoader enabled, deleting a level instance and triggering Undo causes a crash in  ULandscapeComponent::PostEditUndo() The user has provided an example project th ...

Building Geometry Stops UTickableWorldSubsystem Ticking

UE - Gameplay - Jan 13, 2025

Can be mitigated by reopening the Level. There is a repro project provided by the licensee on the case ticket. ...

Sequencer shot blend will have incorrect blend time if play rate of sequence is changed.

UE - Anim - Sequencer - Jan 7, 2025

When there is a blended camera cut and the sequences playrate is changed, the camera blend time will not match the new rate and play incorrectly. ...

Building Geometry Stops UTickableWorldSubsystem Ticking

UE - Gameplay - Jan 31, 2025

Can be mitigated by reopening the Level. There is a repro project provided by the licensee on the case ticket. ...

Mover plugin: Crash on UFloorQueryUtils::ComputeFloorDist() and other utility functions that assume the pawn uses a UCapsuleComponent

UE - Gameplay - Player Movement - Mover - Dec 4, 2025

The following functions have been found to perform unchecked casts of the pawn's "UpdatedComponent" to class UCapsuleComponent, possibly resulting in crashes:UFloorQueryUtils::ComputeFloorDist()UGro ...

"Could not find static actor" errors on standalone editor client when connecting to PIE server

UE - Networking - Iris - Feb 4, 2026

This seems to be due to how FObjectReferenceCache and UEngineReplicationBridge handle remapping object paths for PIE. When creating the object reference handle, the object’s path should get renamed ...

Certain Projects crashes on Start AR on iOS

UE - Platform - XR - Jun 11, 2025

Repro rate 5/5 Project crashes on pressing "Start AR" in ARDebugCheck, on "Begin Scan" in Handheld AR Template and on "Start AR" in ARImageDetection. Issue also occurs on ARVideoSettings and ARSave ...

GroomComponent: SetVisibility(false) causes per-frame simulation reset instead of stopping it

UE - Simulation - Visual - Mar 12, 2026

UGroomComponent::TickComponent sets bResetSimulation = true every frame when the component is not visible. This causes NiagaraDataInterfaceHairStrands to triggering a full simulation reset every fra ...

Performance will drop in PIE if simulate physics is toggled rapidly on an actor with attached components

UE - Gameplay - Nov 3, 2015

Performance will drop in PIE if simulate physics is toggled rapidly on an actor with attached components User Description: Simulating physics for Primitive components causes severe performance dr ...