Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key causes a memory leak

UE - Framework - Blueprint - Apr 15, 2025

When Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key, the function construct the default structure in-place on the given pointer without destroying the object. This behavior ca ...

AttachRootComponentToActor being used over a network can cause an Ensure (previously an Assertion) to be triggered.

UE - Gameplay - Jan 11, 2016

This is a continuation of [Link Removed]. The previous ticket changed an Assertion to an Ensure in order to stop a crash from occurring, and stated that a more complete fix would be coming in 4.10. ...

Material expression called Compiler->TextureParameter() without implementing UMaterialExpression::GetReferencedTexture properly

UE - Rendering Architecture - Materials - Apr 27, 2022

when trying to replace a Material Function instance, with another instance, as the base color of a material within the Material Graph, the editor crashes with the following error:Assertion failed: ...

Float Curve evaluation may yield completely wrong results due to floating-point precision issue

UE - Anim - Runtime - Oct 31, 2024

Note: This is possibly related to [Link Removed]. For some inputs, function UE::Curves::WeightedEvalForTwoKeys() inside file "CurveEvaluation.cpp" can incorrectly return the value of the first key, ...

GAS: GameplayCueNotify OnActive executed twice for Duration GEs on Standalone+ListenServer

UE - Gameplay - Gameplay Ability System - Aug 2, 2023

When playing Standalone or as Listen Server, whenever a GameplayEffect with a duration is applied that fires gameplay cues, the server will locally execute OnActive twice on GameplayCueNotify_Actors ...

Dirty Actors in WP lose their actor folder in the outliner (and cause warnings) on PIE

UE - World Creation - Worldbuilding Tools - World Partition - Mar 20, 2023

From Licensee: You can reproduce this in stock by doing the following:Make a new 5.1 project with a new WP map (it can be empty)Put some actors in some folders in the outliner and save them/reload ...

Import Source disappears in Textures after loading asynchronously loaded level

UE - Editor - Content Pipeline - Import and Export - Dec 15, 2015

It looks like when reimporting a texture asset into the engine after loading a level, you will be confronted with the File Selection box and not the reimport successful notification. In fact if you ...

Crash when using Property Access node on Animation Blueprint (repro based on Lyra Starter Game animation layers)

UE - Anim - Runtime - Jan 24, 2024

When using the Property Access node on Animation Blueprints to gain performance by better exploring parallel processing, it is possible that the underlying accessed property or any intermediate acce ...

Fracture Mode > "Remove-On-Break" setting: Cluster Crumbling causes flickering

UE - Simulation - Physics - Destruction - May 10, 2025

Fracture Mode > "Remove-On-Break" setting: Cluster Crumbling causes flickering. Once the Remove-On-Break Cluster Crumbling effect is activated, there is a small delay between the disappearance of th ...

Crashes when attempting to use an Instanced Struct inside Control Rig / Rig VM

UE - Anim - Rigging - Control Rig - Mar 17, 2025

Currently, the Control Rig Editor allows the user to use the "Instanced Struct" type, for example for a variable or function input/output. However, this type does not seem to be properly supported ( ...