MID TextureCollections don't work with Post Process Overlays

UE - Rendering - RHI - Aug 24, 2026

TextureCollectionParameters in a material assigned to a Post Process Overlay are not overridden by a MID because CopyInterpParameters in Engine\Source\Runtime\Engine\Private\Materials\MaterialInsta ...

Unable to kill UnrealBuildTool, UBT no longer propegates sigterm

UE - Core - Cpp Tools - UnrealBuildTool - Aug 24, 2026

When UBT is launched through one of the standard wrapper scripts, Ctrl-C no longer cancels the build. The `dotnet UnrealBuildTool.dll` process and its compile actions keep running to completion in t ...

VRS Cvar Crash during CollectPSOInitializers when CVarEnableVRS.GetValueOnRenderThread() causes Ensure failure

UE - Rendering - RHI - Aug 21, 2026

We are running into an ensure that is triggered when CVarEnableVRS.GetValueOnRenderThread() is called on the game thread from FVariableRateShadingImageManager::IsAttachmentVRSEnabled. This happens ...

FCameraShakePreviewer retains world-outered UCameraShakeBase instances indefinitely, fataling CheckForWorldGCLeaks on editor map change

UE - ACT Character - Sequencer - Aug 21, 2026

FCameraShakePreviewer is an FGCObject that strongly references the UCameraShakeBase instances it previews, and creates them outered to the previewed UWorld. Nothing releases them on world teardown, ...

Chaos: geometry collection with One Way Interaction never breaks from its own collisions

UE - Runtime - Simulation - Aug 21, 2026

A geometry collection with One Way Interaction Level set to 0 never breaks from its own collisions. It falls, lands, and stays intact no matter what it hits. Set the level to -1 (feature off) and ch ...

UCharacterMovementComponent::CapsuleTouched crashes on UGeometryCollectionComponent overlap (unchecked USkinnedMeshComponent cast)

UE - Runtime - Character - Aug 21, 2026

Summary: Confirmed that this exists in latest as well as 5.8 which is the origin or both tickets. This is a regression from 5.7 - although it looks like the guard was not aiming specifically to catch ...

Interchange GLTF importer truncates skeletal mesh bone influences to 4 per vertex

UE - Editor - Open File Formats - Aug 21, 2026

cf https://forums.unrealengine.com/t/interchange-gltf-importer-truncates-skeletal-mesh-bone-influences-to-4-per-vertex/2745391/2 Original message The UE5 Interchange GLTF importer appears to trunc ...

NavMoverComponent ConsumeNavMovementData returns true on any repeat call within the same game frame

UE - Gameplay - Player Movement - Mover - Aug 20, 2026

UNavMoverComponent::ConsumeNavMovementData returns true on any repeat call within the same game frame, even when there is no nav movement to report. Callers that trust the return value then act ...

Enhanced Input Gesture keys (Pinch/Rotate/Flick) never release after touch ends — regression in 5.8

UE - Gameplay - Input - Aug 20, 2026

POST LINK: https://forums.unrealengine.com/t/enhanced-input-gesture-keys-pinch-rotate-flick-never-release-after-touch-ends-regression-in-5-8/2745006 POST BODY:Summary An Input Action mapped directl ...

"Landscape Layer" Doesn't appear in LandscapeMode even when the landscape is assigned a Layer-Based Material

UE - Graphics Tools - Terrain - Aug 19, 2026

POST LINK: https://forums.unrealengine.com/t/bug-ue5-8-1-landscape-layer-doesnt-appear-in-landscapemode-even-when-the-landscape-is-assigned-a-layer-based-material/2745109 POST BODY:Summary[Bug][UE5 ...