Animation compression deadlock

UE - Anim - Runtime - Anim Blueprints - Feb 5, 2026

The deadlock occurs when attempting to cancel compression during animation sequence destruction. The compression thread ends up deadlocking with the game thread, which is the one requesting the canc ...

Possible to duplicate shot tracks

UE - Anim - Sequencer - Feb 5, 2026

Multiple shot tracks are a problem source, and UE seems to try and pre-empt them by disabling the menu option to add a second one when one is already in there. Duplication, however, is still permitt ...

Adding weights to bones doesn't properly update skeltree

UE - Anim - Rigging - Skeletal Editor - Feb 5, 2026

Mover | FStanceModifier adjustment teleport on Crouch/Uncrouch can fail when child components intersect world

UE - Gameplay - Player Movement - Mover - Feb 3, 2026

Context When crouching and uncrouching with Mover’s DefaultMovementSet, the pawn capsule’s half height is changed. This behavior mimics the CharacterMovementComponent. To ensure the pawn’s feet sta ...

Mass entities initializing fragments on the incorrect archetypes due to shared CreationContext

UE - AI - Mass - Feb 3, 2026

UMassAgentSubsystem::HandlePendingInitialization creates a single FEntityCreationContext that is reused across all iterations of the PendingAgentEntities loop. When SpawnEntities eventually calls in ...

Tooltips not appearing in Editor when hovering over assets due to Slate Cursor Move settings

UE - Editor - UI Systems - Slate - Feb 3, 2026

User noticed that when Slate.EnableSyntheticCursorMoves is set to false the editor UI tooltips no longer display. As noted by the user, modifying Slate.CursorSignificantMoveDetectionThreshold to at ...

Material Functions are incorrectly listed in the Layer Asset list

UE - Rendering Architecture - Materials - Feb 3, 2026

Since UE 5.7, Material Functions are included in the Layer Asset list of the Material Layers of an instanced material using material layers. It is also possible to drag and drop Material Functions ...

“S” key fails to add key to transform when additive track Is locked

UE - Anim - Sequencer - Feb 2, 2026

When an additive transform track is locked, pressing the “S” key does not add a new key to the sequence. No key is added to either the additive track or the base transform track. What the user expe ...

MRQ reports missing frames when rendering multiple cameras on a Sequencer camera track with Temporal Sample Count > 1

UE - Virtual Production - Tools - MRQ - Feb 2, 2026

If there are multiple cameras in the Sequencer camera track, everything works correctly when the Temporal Sample Count for anti-aliasing is set to 1. However, when it is set to 3, the following erro ...

Hard shadow edges appear when using Displacement Fade on a Nanite tessellated landscape

UE - Graphics Tools - Terrain - Feb 2, 2026

A hard shadow edge occurs when displacement fade is enabled on a Nanite landscape with tessellation. This occurs on the edge between two clipmap levels of the VSM. The artefact can be somewhat red ...