BlackboardComponent observer can be called for the wrong key

UE - AI - BehaviorTree - Feb 7, 2023

We need to, at least, prevent this by clearing observers when running a new BT using a different blackboard. Must also think that this might affect licensees relying on the current behavior (might h ...

GameplayAbilitiesSystem: GameplayCues OnRemoved never firing

UE - Gameplay - Gameplay Ability System - Nov 15, 2023

This behaviour was introduced in the following changelists in 5.3: CLs 25371706 and 25407985 https://github.com/EpicGames/UnrealEngine/commit/6e985ceeb98bc0d166756ccd3e3c0b0350d02265https://github. ...

TranslucentVolumeAmbient is darkened in InjectTranslucencyLightingVolume pass when using VSMs with r.Shadow.Virtual.ForceOnlyVirtualShadowMaps is Off

UE - Graphics Features - Shadows - Nov 18, 2024

CSM targets are still created and affect the InjectTranslucencyLightingVolume pass when moving in a project that only uses VSM causing over brightening of fog planes and other translucent meshes. r ...

Popping Ribbon UVs

UE - Niagara - Mar 10, 2025

Please see the Additional Link for related UDN information. The UV popping described can be subtle, depending on settings; it's affected by spawn rate and GPU vs CPU. The popping shown in the gif t ...

Adding SmartObjectZoneAnnotationComponent to a blueprint actor causes a crash when building the package

UE - AI - SmartObject - Jan 30, 2025

If placing an actor with SmartObjectZoneAnnotationComponent added to blueprint actor in a level, it will crash when the level open. As a workaround, adding SmartObjectZoneAnnotationComponent to the ...

Using FEditorModeID for the "Mode" console command does not switch the modes tab

Tools - May 10, 2016

Using the FEditorModeID for the different editor modes does not affect actual modes available in editor Modes tab. Example: Command "Mode EM_Foliage" does not switch to the foliage mode Workaround ...

Cursor breaks viewport when using Widget Render Transform Scale

UE - Editor - UI Systems - Mar 14, 2017

The viewport cursor will continue to display off of the actual viewport until the widget ends if the border component actually extends. This has not been tested with any other template. Regression ...

Packaging Fails in a C++ Project with a Project Name Containing an Apostrophe

UE - Foundation - Core - Mar 16, 2017

Packaging fails in a C++ project when the Project Name field (Project Settings->Description->Project Name) contains an apostrophe. I've attached the logs from the 4.15 version of the project. Thi ...

Spectator Pawn cannot be added to level by dragging into viewport

Tools - Mar 23, 2017

Spectator Pawn cannot be added to level by dragging into viewport but can be added by using place actor in the level viewport. Regression: This issue occurs in 4.13.2, 4.14.3, and 4.15.1 of the Bin ...

Packaging a Project With Nativize Blueprints Enabled Fails With Setter for an Array of Classes

UE - Gameplay - Blueprint Runtime - Mar 23, 2017

Packaging failure occurs with nativize blueprints enabled when you have an array of classes and you try to set it with an array from an instance of a native C++ class. Found in 4.15.1. Reproduced i ...