UAbilityTask_SpawnActor::BeginSpawningActor may return true when SpawnedActor contains stale value

UE - Foundation - Mar 15, 2026

UAbilityTask_SpawnActor::BeginSpawningActor assumes the incoming AActor*& SpawnedActor parameter is nullptr if no actor was spawned, but it does not initialize the parameter at the start of the func ...

StateTree: While editing State Parameters or exposed properties of a Condition/Task, an ensure() fires when editing inputs of a Property Function bound to an array element

UE - AI - StateTree - Mar 5, 2026

Consider an array property that can be edited in the StateTree editor. This can be a State Parameter or an exposed property of a Condition or Task, for example. Each element of the array can be boun ...

Engine crashes when renaming assets inside an L10N folder.

UE - Editor - UI Systems - Localization - Mar 3, 2026

The engine crashes when renaming a localizable asset inside an L10N folder. The engine attempts to associate it with the original localizable asset, but it is unable to find it and ends up accessing ...

InvariantLeft and InvariantRight justification mispositions wrapped multi-line text

UE - Editor - UI Systems - Feb 26, 2026

When a UMG Text widget is set to Auto Wrap and uses InvariantLeft or InvariantRight, the wrapped visual lines are positioned differently than expected compared to Left/Right. In the current engine ...

Niagara GPU Distance Field collision uses only the first view in split-screen, causing collision to drop out for other players when view 0 loses Global DF coverage

UE - Niagara - Feb 17, 2026

In split-screen, Niagara GPU Distance Field collision appears to be evaluated against only the first view passed into the Niagara GPU sim (view index 0), rather than per split-screen view. Because G ...

Iris - Initially dormant actors not replicated if dormancy is not enabled

UE - Networking - Iris - Feb 16, 2026

With dormancy disabled, it seems that actors marked as dormant are not registered as expected with Iris. Even if the actor is woken up or flushed before making changes to its properties, the client ...

Iris - HitObjectHandle not resolved when receiving FHitResult

UE - Networking - Iris - Feb 12, 2026

This seems to occur due to an interaction between how Iris handles serializing the FGameplayAbilityTargetData_SingleTargetHit struct and how the FActorInstanceHandle HitObjectHandle in the FHitResul ...

Attached actors have AttachmentReplication marked as dirty every net update

UE - Networking - Feb 11, 2026

In AActor::GatherCurrentMovement, bWasAttachmentModified will be set to true if the actor’s root component has an AttachParent, even if none of the values in the AttachmentReplication struct have ch ...

Division by zero causing NaN/Inf on USkeletalMeshComponent::UpdateRigidBodyScaling() when setting scale to zero and back

UE - Simulation - Core - Feb 11, 2026

Up to UE 5.5, skeletal mesh physics did not get updated when the component's scale changed. This was improved on January 2025 with CL 39190335, which addressed [Link Removed] ...

FDetailGroup::AddGroup does not correctly apply the default expansion state for DetailGroups

UE - Editor - Workflow Systems - Feb 10, 2026

There is a bug affecting DetailGroups in the engine. When adding child DetailGroups to a parent DetailGroup, the expansion state does not behave as expected and ignores the flags intended to control ...