Interaction between sublevels and LevelSequences can break actors attachments hierarchy of the sublevel.

UE - World Creation - Worldbuilding Tools - Aug 6, 2025

Having a LevelSequence opened and unhiding a sublevel can break the attachment hierarchy of the actors that are inside the sublevel. This also affects to the sublevel asset itself. ...

DataLayer: Duplication a GroupActor is broken

UE - World Creation - Worldbuilding Tools - Data Layers - Aug 5, 2025

The result of the duplication operation is that the Actors in the new group are part of the DataLayer but the new GroupActor is not.  ...

NavMesh generation should not care for Actors that are hidden in the Editor.

UE - AI - Navigation - Aug 5, 2025

The problem is that the Cube is still loaded but "HiddenEd". It's AActor::bHiddenEdLayer property is set to true by the WorldPartition System. The Actor is dirty which makes the WP system pin it (wo ...

Environment Query System (EQS): EnvQuery runtime template object can be created with a non-unique name, corrupting the EnvQueryManager cache

UE - AI - Aug 5, 2025

On file [Engine\Source\Runtime\AIModule\Private\EnvironmentQuery\EnvQueryManager.cpp:812], function UEnvQueryManager::CreateQueryInstance() uses StaticDuplicateObject() to create a new UEnvQuery* (d ...

SSR doesn't reflect Skydome Mesh/Material correctly in Vulkan mobile preview

UE - Platform - Mobile - Aug 4, 2025

5.6[Image Removed] 5.5[Image Removed][Link Removed] ...

LiveCoding fails when DynamicDebugging is enabled

UE - Foundation - Cpp Tools - Live Coding - Aug 4, 2025

If DynamicDebugging is enabled, the output extension in the LiveCoding manifest is ".alt.dll", but the actual built DLL does not include ".alt" in its name. This mismatch causes an error. ...

SkinWeightsAsVertexMask in DeformerGraph does not respect SkinWeightProfile

UE - Anim - Rigging - Deformer - Aug 1, 2025

The WeightBuffer passed to the shader does not reflect the SkinWeightProfile. The work around is : void FOptimusSkinWeightsAsVertexMaskDataProviderProxy::GatherDispatchData(FDispatchData const& In ...

Crash when displaying lumencards on map with many objects

UE - Graphics Features - Lumen - Aug 1, 2025

There is a thread conflict between FRDGBuilder execution in Background Worker and LumenVisualizer's LumenCard add/delete process. When lumen cards are displayed in a scene with many objects, a crash ...

Crash when changing parent of Material Instance with Layered Materials and viewing Layer Parameters

UE - Rendering Architecture - Materials - Aug 1, 2025

Reparenting a MaterialInstance that uses Material Layers to another instance with a different layer configuration can cause the editor to crash when opening the Layer Parameters tab. This appears to ...

If any light source is deleted, and a single light has its visibility state changed in LightMixer, all the other lights in the scene that were invisible turn visible

UE - Virtual Production - Tools - Jul 31, 2025

If any light source is deleted, and a single light has its visibility state changed in LightMixer, all the other lights in the scene that were invisible turn visible. The behavior only shows after d ...