Renaming a Blackboard Key removes it's references in the Behavior Tree

UE - AI - Jan 27, 2015

Renaming a Blackboard Key removes it's references in the Behavior Tree ...

Parent component visibility in a child blueprint isn't reflected in a launched project.

UE - Gameplay - Blueprint - Mar 5, 2015

Parent component visibility in a child blueprint isn't reflected in a launched/packaged project. ...

Niagara - When Interpolated Spawning is disabled, the first frame of each particle unexpectedly does not take into account the Particle Update stage

UE - Niagara - Feb 28, 2025

Foreword: Even if the behavior described here is by design, it is rarely (if ever) expected or desired. This was discussed and agreed to be treated as a bug. Explanation below. When interpolated sp ...

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

UE - Editor - Workflow Systems - Feb 20, 2024

UDN Issue: [Link Removed] ...

Physics Constraints do not have the same values if they are part of an 'Always Loaded' level

UE - Gameplay - Dec 3, 2014

Physics Constraints do not have the same values if they are part of an 'Always Loaded' level. They will work correctly in the Persistent level and a level that is Streamed in. This becomes problem ...

In Editor, Blueprint resources are not freed up when the Blueprint is closed

UE - Framework - Blueprint - Feb 16, 2024

It appears that the preview scene used to render thumbnails is not destroyed after a thumbnail is rendered, even after the blueprint editor is closed and GC is run. Also found in Release-5.4, CL: 31 ...

StructUtils plugin's `FInstancedStruct` in a CPP-defined struct in a `TArray` on an actor component defined in CPP and implemented in BP. Populating the instanced struct in an actor BP's class defaults breaks serialization of the class defaults.

UE - AI - May 30, 2025

Context Instanced structs are great for holding simple data with the main advantage they have is a low memory overhead unlike instanced objects. Problem The problem is in StructUtils plugin's `FIns ...

Animating blueprint mesh duplicates uncontrollably

UE - Gameplay - Components - Apr 15, 2015

When animating within a blueprint of a subclass created in c++, the animating mesh replicates itself uncontrollably. Added to .h: UPROPERTY() UBoxComponent* BoxComp; UPROPERTY() USkeletalMeshCompo ...

Enum Meta is being ignored when project is packaged

Tools - Nov 4, 2014

When using UMeta on Enums, text is ignored when doing Enum to String on a packaged project. ...