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 ...

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 ...

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 ...

After Seamless Server Travel, the Client cannot move the character or see the Server character

UE - Networking - Jul 9, 2015

After Seamless Server Travel, the Client cannot move the character or see the Server character. On the Server, the Client character appears to be falling in place. Tested in both first and third per ...

Destructible attached with a Physics Constraint have inconsistent physics

UE - Simulation - Physics - Destruction - Jul 26, 2016

Destructible attached with a Physics Constraint have inconsistent physics compared to a standard Static Mesh. This is also sometimes prevalent with Destructibles that aren't attached with a Physics ...

changing localization does not change text in PIE

Tools - Sep 10, 2015

When switching localization for testing, text does not change language in PIE. ...

AbilitySystemComponent::NotifyAbilityEnded Can Crash due to Callbacks Invalidation Specs

UE - Gameplay - Gameplay Ability System - Oct 11, 2023

Pasting from the UDN: Unsafe code in AbilitySystem can lead to crash when granting an ability inside OnAbilityEnded Hello. We just ran into a crash. After investigation, it seems to be caused by ...

Renamed Enums displayed in Standalone game will show the original default name instead

UE - Gameplay - Blueprint - Mar 18, 2015

Renamed Enums displayed in Standalone game will show the original default name instead. ...