ensure(PinHelpers::UnresolvedPins.Num() == 0); fails after undoing in the editor

UE - Framework - Blueprint Editor - Sep 6, 2025

The underlying cause is some edge case involving a math expression node, which does some perhaps naive things with a contained graph. ...

DirectoriesToAlwaysCook in platform specific configuration files are ignored by the cook process

UE - Platform - Console - Sep 5, 2025

When DirectoriesToAlwaysCook is placed in a platform-specific configuration file, the cook process does not read that entry when cooking content for that platform. The editor is aware of the platfo ...

Crash when calling SetState inside state machine OnUpdate

UE - Anim - Sep 5, 2025

The crash happens when SetState is called inside the function bound to OutputAnimationPose’s OnUpdate in the animation state. This way of using Set State node is the same as shown in the official do ...

Lumen Translucency lighting vs opaque mismatch is larger than expected

UE - Graphics Features - Lumen - Sep 5, 2025

The licensee's VFX team has been struggling with getting their Niagara systems with translucent materials to fit into the environments they are being used in. In a project with default settings, the ...

Sequencer is not taking into account the TransformOriginOffset of the level sequence actor.

UE - Anim - Sequencer - Sep 3, 2025

When a level sequence actor has camera's marked for preroll in it and information is gathered for a camera cuts location to send to the streaming manager, it does not take into account the Transform ...

Invalid GUIDs on new material instance parameters cause overrides to break on base param rename

UE - Rendering Architecture - Materials - Sep 3, 2025

When a parameter value is assigned on a newly created material instance (constant or dynamic) using Set***ParameterValueInternal, the parameter’s ExpressionGUID is left invalid (0,0,0,0). Parameter ...

Negatively scaled box collisions render back faces in Player Collision debug view

UE - Simulation - Visual - Sep 1, 2025

The player collision debug visualization for negatively scaled boxes is rendering the back faces, not the front faces. The debug primitives are rendered via the dynamic mesh builder. FDynamicMeshBui ...

GeometryCollectionPhysicsProxy::FieldParameterUpdateCallback() not removing invalid Commands, leading to performance issues

UE - Simulation - Visual - Aug 30, 2025

GeometryCollectionPhysicsProxy::FieldParameterUpdateCallback() not removing invalid Commands, leading to performance issues. The licensee has provided their analysis: We seem to have stumbled acro ...

UMG Retainer Box renders incorrect colors with Color Vision Deficiency enabled

UE - Editor - UI Systems - UMG - Aug 27, 2025

When using a Retainer Box in UMG with Color Vision Deficiency enabled, the content inside the Retainer Box is rendered with incorrect colors compared to the rest of the UI. This bug is present in UE ...