Ensure triggered in FBoundsCacheElement::GetValue when adding ISM instances in Construction Script

UE - AI - Oct 8, 2025

An ensure is triggered in FBoundsCacheElement::GetValue when adding instances to an InstancedStaticMeshComponent inside a Blueprint’s Construction Script. This occurs when the ISM component is navig ...

CppCompileWarningSettings.NonInlinedGenCppWarningLevel messages should contain Warning\Error

UE - Foundation - Cpp Tools - UnrealBuildTool - Oct 8, 2025

The messages emitted when CppCompileWarningSettings.NonInlinedGenCppWarningLevel is set to Warning\Error should contain the literal so the tools pick them up and react accordingly. From the EPS c ...

Crash at compile time when using a VariableSet node with a local variable created by pasting a private property

UE - Framework - Blueprint - Oct 7, 2025

When a property is created in this way, a local variable with a Private flag is generated. Since such a variable is generally not desirable, it would be better to remove the Private flag upon pastin ...

HZB Occlusion causes large stalls on the render thread

UE - Rendering Architecture - RHI - Oct 7, 2025

HZB Occlusion causes large stalls (greater than 5ms seen) on the render thread due to an RHI flush. This is caused by the following code in FDynamicRHI::RHIMapStagingSurface_RenderThread which force ...

Landscape Textures Patches issue when using "Texture Backed Render Target" as the Height Patch Source Mode where Landscape patches are not applying properly the first time a level is opened after restart

UE - Graphics Tools - Terrain - Landscape - Oct 6, 2025

Context: Landscape patches are components that can be attached to meshes to affect the landscape as the mesh is repositioned. Problem: The problem is that when using "Texture Backed Render Target" ...

Incorrect Lumen Scene direct lighting when objects behind masked landscape

UE - Graphics Features - Lumen - Oct 5, 2025

When objects are placed behind or beneath a masked landscape and r.Lumen.HardwareRayTracing.SurfaceCacheAlphaMasking is enabled, the direct light evaluation is incorrect. There are two workarounds, ...

TMaps do not function as expected in the details panel when then TMap variable is in a blueprint component

UE - Framework - Blueprint - Oct 3, 2025

The default element can be added multiple times and changing the value from the drop down. ...

WP: The Generation log report doesn't contain the result of the ActorDescViewMutators

UE - World Creation - Worldbuilding Tools - World Partition - Oct 3, 2025

OculusOpenXRLoader.build.cs should be part of all InstalledBuild

UE - Foundation - Build - Rocket (Installed Engine) - Oct 2, 2025

The OculusOpenXRLoader module is only required on Android but it should be possible to reference it from any project\plugin that doesn't target that platform.  The user that found the problem is ...

Recompiling an ABP that another ABP has a Property Access dependency on without recompiling/linking the other causes a crash

UE - Anim - Runtime - Anim Blueprints - Oct 2, 2025

The crash comes from the pointers in FAnimSubsystem_PropertyAccess::Library::Indirections in the layer ABP from pointing to old/invalid functions and properties from the trash ABP_Manny, as they hav ...