Initialize_AnyThread and CacheBones_AnyThread can be called multiple times on Saved Pose nodes in linked anim graphs

UE - Anim - Runtime - Jun 13, 2025

Initialize_AnyThread and CacheBones_AnyThread can be called repeatedly on sub-graphs below Saved Pose nodes when they are part of a linked anim graph and the main anim graph has yet to be initialize ...

FBlackboardKeySelector filters aren't applied when recompiling blueprint if a behavior tree asset containing the blueprint added as a service is closed, or if the blueprint is reparented.

UE - AI - BehaviorTree - Sep 24, 2025

Context In Behavior Trees, BT Services can be added to nodes. Those services can have configurable FBlackboardKeySelectors. BlackboardKeys are variables on a blackboard that the behavior tree can r ...

Inaccurate motion vectors when using different position binding in renderer

UE - Niagara - Rendering - Jul 27, 2023

Even though the particles are not moving, and the velocity is zero, the output motion vectors are non-zero. This seems to only happen if using two sources of particle positions.  ...

After breaking a level instance without Actor Folders, moving its actors between folders of the world-partition map does not work correctly

UE - World Creation - Worldbuilding Tools - World Partition - Jan 29, 2024

If a standard level (without Actor Folders enabled) is added to a world-partition map (with Actor Folders enabled) as a Level Instance, and then that instance is "broken" so that its actors are inco ...

Exponential Editor Slate Performance Cost When Editing An Asset With Nested Instanced Structs

UE - Editor - Workflow Systems - Feb 20, 2024

UDN Issue: [Link Removed] ...

Replicating a non-root component with simulate physics enabled causes the component to be in the wrong place on spawn, on clients.

UE - Simulation - Gameplay - Jan 20, 2025

When a BP spawns another, if the spawned Actor has a non-root child component that is simulating physics, on clients, immediately after spawn, the child component will have the world position double ...

Internal Compiler error when calling a custom enum in a struct from a blueprint macro

UE - Gameplay - Blueprint - Aug 6, 2015

If a macro is referencing a custom enum within a struct and compiled after another output pin is removed, an internal compiler error will appear and the blueprint will not compile. ...

Crash in UEditorEngine::ToggleBetweenPIEandSIE when ejecting from Play In Editor while starting a multiplayer session

Tools - Aug 24, 2020

UE4Editor crashes when we eject from a Play In Editor session while starting a multiplayer session. ...

Crash with for loop and TArray in constructor to generate multiple StaticMeshComponents

UE - Foundation - Core - Apr 20, 2015

Using a TArray to store multiple components being setup inside a for loop of a constructor will crash on project open. Crash Reporter: [Link Removed] ...

Foliage rendering issues when using both Density Scaling and MaxWorldPositionOffsetDisplacement

UE - World Creation - Worldbuilding Tools - Foliage - Aug 29, 2024

When a material with WPO effects and MaxWorldPositionOffsetDisplacement is applied to a foliage mesh, foliage applied to a map will no longer work as expected with density scaling, especially after ...