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 ...

Construction Script using GetSizeX/Y from Texture 2D reference returns Divide By Zero Warning when Packaging

UE - Graphics Features - Jul 21, 2016

A user has found and reported a divide by zero warning within the Construction Script when packaging for Windows. This does not occur while in the editor as when you begin moving around the blueprin ...

Joining a session in PIE with Auto Connect To Server disabled will crash PIE

UE - Networking - Nov 11, 2015

Joining a session in PIE with Auto Connect To Server disabled will crash PIE. Note: this is not specific to the Multiplayer Shootout project used in the repro steps; this will occur in any project ...

[Sound Cue][Blueprint API] - Setting a parameter value a second times does not work

UE - Audio - Apr 9, 2022

Setting a parameter on a Sound Cue from Blueprints more than once is not working. The first time a parameter is set works, but any following sets are ignored. This is a regression and does not occu ...

Implied Decal Blend Modes don't properly account for Material Attributes usage

UE - Graphics Features - Sep 28, 2021

I've attached a project with the necessary materials that demonstrate this issue. I would expect that just because a Set Material Attributes node is inside a material graph it wouldn't affect the de ...

Particles Do Not Obey Lighting Channels

UE - Niagara - Apr 17, 2018

Particle systems ignore lighting channels - no matter what channel a light is on (even if no channels are selected), it will affect lit particles. Changing lighting channels on the particle itself h ...

Lighting on Paper 2D Tile Maps is Broken

UE - Graphics Features - May 8, 2018

In 4.18.3 this feature is working. In 4.19.2 the feature is broken. Per User: Half of the Lights Cone or Sphere will properly interact with the TileMap as intended, the other half will not for wha ...

WorldPartitionConvertCommandlet hits an assert when converting a persistent level that contains a sub-level with a landscape

UE - World Creation - Worldbuilding Tools - Nov 7, 2025

Context: The Window tab allows a user to open the Levels window in order to add a sub-level to a persistent level. For Unreal Engine 5.0 and beyond, World Partition has made the Levels window obsole ...

Sequencer Render: Animation not updating for a moment on camera cut

UE - Anim - Sequencer - Mar 17, 2017

When rendering from sequencer to an image sequence, character animation stops for 2 frames after a camera cut. This hitch does not occur when playing the sequence in PIE I've attached some sample d ...

Long thin spinning objects take too long to stop spinning

UE - Simulation - Core - Jun 5, 2023

See the SpinningObjectStability test map in the Physics Sandbox. [Link Removed] It's not clear if this is a bug or a side effect of some of our solver shortcuts (e.g., omission of the precession te ...