Unreal Engine Issues
Unreal Engine Issues
If a child blueprint class has an Instanced/EditInlineNew object property, that property will always be detected as changed by the property editor (i.e. it will show a "Revert" arrow on that property), even if its properties are identical to the parent.
UE - Framework - Blueprint Editor - Dec 17, 2025Context: Blueprint classes can use Instanced/EditInlineNew object property specifiers to create and edit subobjects directly in the editor. Problem: If a child blueprint class has an Instanced/Edit ...
ActorComponents registered with wrong world from UWorldPartition::ApplyRuntimeCellsTransformerStack
UE - World Creation - Worldbuilding Tools - World Partition - Dec 17, 2025There is a risk of actor components registering with the wrong world when reconstructed from UWorldPartition::ApplyRuntimeCellsTransformerStack. The repro case is arguably a bad usage, but it was th ...
Viewport stuttering during orbit/zoom navigation
UE - Graphics Features - Dec 17, 2025Received a report of persistent stutters in the editor when trying to navigate in the viewport, including asset editor viewports like the Skeletal mesh editor and control rig editor. Hardware used ...
A chaos vehicle that moves at very high speeds with CCD enabled on the vehicle sometimes has a collision response that is abnormal where the vehicle loses a significant amount of speed when colliding with dynamic objects configured as One Way Interaction
UE - Simulation - Gameplay - Dec 16, 2025Context: Continuous Collision Detection (CCD) is being used on a Chaos Vehicle to avoid tunneling issues with certain surfaces as it prevents any missed collisions between fast moving particles and ...
ISM Cell Transformer breaks component hierarchy when child component are transformed
UE - World Creation - Worldbuilding Tools - World Partition - Dec 15, 2025This case is related to [Link Removed] but is not a duplicate. Please make sure to download the attached project as it's different than the one in the other case. The problem here is that the ...
[AI] StateTree fails to compile after copy/pasting a state with a task that binds to required event on the state's enter conditions
UE - AI - StateTree - Dec 14, 2025StateTree appears to keep an incorrect reference to the event from the source tree rather than re-establishing the property binding to the new tree's event. This happens when copy/paste of the state ...
OcclusionFeedback may not be performant for primitives with large screensize
UE - Platform - Mobile - Dec 13, 2025A licensee reported that the performance could be worse in some scenarios (probably a small scene with large objects) with OcclusionFeedback enabled ( 20fps up if disabled), tested on a Qualcomm 870 ...
[3ds max] Some geometry will display in all black in Path Tracer renders
UE - Editor - Content Pipeline - Datasmith - Exporters - Dec 12, 2025Reported in SF [Link Removed] Some geometry from 3ds Max will display as all black when viewed in Path Tracer rendering. This effect is visible in both UE and Twinmotion. This was tested with Data ...
Iris - Ensure hit when destroying a torn off actor from AActor::TornOff
UE - Networking - Iris - Dec 11, 2025As of CL 42014318, StopReplication requests that occur during ReceiveUpdate are delayed until all received data from the update is finished processing, including if the actor is torn off. However, i ...
Iris - BeginPlay not called on client for statically placed, low-priority replicated actor
UE - Networking - Iris - Dec 11, 2025On the client, NotifyBeginPlay is triggered via AGameStateBase::OnRep_ReplicatedHasBegunPlay. However, if a replicated actor is waiting on its initial replicated state to be received and applied (bA ...