Character unnecessary step down during PHYS_Flying mode

UE - Gameplay - Player Movement - Jan 15, 2026

When MovementMode is set to PHYS_Flying, the character may unexpectedly step down by MaxStepHeight when colliding with a wall near a ceiling. This occurs because UCharacterMovementComponent::StepUp ...

Editor ensure in USceneComponent::OnComponentDestroyed during Blueprint compilation GC

UE - Framework - Components - Jan 15, 2026

An editor-only ensure can trigger during BP compilation when garbage collection cleans up transient components created as part of component replacement. During recompilation, old component instances ...

'Hide Unconnected Pins' Button in the Blueprint Node Details Panel Disconnects SubPins with Connections

UE - Framework - Blueprint - Jan 14, 2026

Given a get node with a struct output, if "Split Struct Pin" is used on the struct and one of that struct's outputs are connected to another node, it does not count as a used pin when the base get n ...

HISM flickering when any character is visible

UE - Rendering - Architecture - RHI - Jan 12, 2026

On an NVIDIA GPU, Instanced Static Meshes can flicker when a Groom card or mesh LOD is visible. This appears related to an issue rendering the ISM into the Scene Depth. At the end of the Prepass, t ...

Light Function Materials containing a Texture Sample and Rotator nodes will fail RHI Validation

UE - Rendering - Architecture - RHI - Jan 12, 2026

Using a Light Function Material that contains a Texture Sample and Rotator nodes will cause RHI Validation to fail with the following error: LogOutputDevice: Error: Ensure condition failed: Bindings ...

"Scale for <ComponentName> has a component set to zero, which will result in a bad body instance" warning spam when moving actor instance even with Collision Profile overriden to "NoCollision"

UE - Runtime - Simulation - Jan 12, 2026

When a StaticMeshComponent has a scale component of zero in WorldSpace (after accumulating with the hierarchy from the root to it), function UPrimitiveComponent::OnCreatePhysicsState() logs the warn ...

Lumen Global Distance Field Trace Leaking due to Surface Cache Sampling

UE - Rendering - Graphics Features - Jan 12, 2026

At specific distances from a thin wall, surfaces inside of a sealed chamber can receive indirect lighting from outside, leaking light into the chamber. This appears to be due to how SWRT handles sa ...

GameplayTags meta "Categories" return warning when all categories are not present inside the FGameplayTagContainer

UE - Gameplay - Gameplay Tags - Jan 12, 2026

Categories are not processed correctly for gameplay tags when meta "Categories" is used. Categories filter which categories appear for the mentioned gameplay tag variable and with recent changes, it ...

Temporal blur artifacts on Geometry Cache Components in Blueprint actor

UE - Editor - Content Pipeline - Alembic - Jan 9, 2026

When a Geometry Collection is in a Blueprint, attached to other components, it can render incorrect motion vectors at some angles. In the test project, any angle that is not a multiple of 45 will re ...