same PhysicsAsset refresh multi times when modify multi SkeletalBodySetup properties in same PhysAsset

UE - Simulation - Gameplay - Nov 20, 2025

USkeletalBodySetup::PostEditChangeProperty will call OwningPhysAsset->RefreshPhysicsAssetChange(), if I modify many SkeletalBodySetup properties in same PhysAsset, will cause call OwningPhysAsset-> ...

Build crash when enabling r.CreateShadersOnLoad=1

UE - Rendering - Architecture - Shaders - Nov 10, 2025

When "r.CreateShadersOnLoad" is enabled, cooking will crash due to failure to create a shader. This occurs on //UE5/Release-5.5, CL: 41545209 and //UE5/Release-5.6, CL: 45232827 ...

GAS: FActiveGameplayCueContainer::RemoveCue crash while iterating removals when consecutive Cue tags are conditionally added and the conditional effects removed in ascending order

UE - Gameplay - Gameplay Ability System - Nov 4, 2025

When removing gameplay effects by tag, if the tag that is being removed has other tags that are dependent on it in a cyclical way an "array out of bounds ' error can be triggered. ...

[AI] Gaps between Nav Mesh tiles in World Partition map causing movement issues

UE - AI - Navigation - Nov 4, 2025

Navmesh has seams between some tiles that are actual edges rather than previously found "gaps" where it was a debug rendering issue. Pathfinding does fail between these tiles to go straight across. ...

Body Setup of a Static Mesh with Simple Collision will pass validation, but removing it and using only a Complex collision and setting Collision Complexity "Use Complex as Simple" will fail validation: "Bone None requires at least one collision shape".

UE - Simulation - Gameplay - Oct 20, 2025

Context: By default, Unreal Engine creates both simple and complex shapes, then, based on what the user wants (complex query versus simple query), the physics solver will use the corresponding shape ...

Incorrect Lumen Scene direct lighting when objects behind masked landscape

UE - Rendering - 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, ...

Wrong density calculation in UBodySetup::CalculateMass

UE - Simulation - Core - Sep 29, 2025

Wrong density calculation in UBodySetup::CalculateMass. The licensee has provided the following analysis and suggested fix: In UBodySetup::CalculateMass, the following code is present: // physical ...

Post Process Animation Blueprint Crash When Using Blend Node

UE - Anim - Runtime - Anim Blueprints - Sep 24, 2025

When using a Blend node inside a Post Process Animation Blueprint, the editor crashes while rendering thumbnails. The crash occurs because USkeletonThumbnailRenderer attempts to draw a thumbnail wit ...

When exporting static meshes with bExportSourceMesh enabled, there is a problem where all UVs are fragmented.

UE - Editor - Content Pipeline - Import and Export - Sep 22, 2025

From customer: "In the StaticMesh Export option, when bExportSourceMesh is set to True, exporting StaticMesh Assets and importing them into DDC tools such as 3dsMax or Maya results in the UVs being ...

Controller::OnPossessedPawnChanged broadcasts (Pawn->null) but not (null->Pawn) during AGameModeBase::RestartPlayer()

UE - Gameplay - Sep 17, 2025

Context AController has a blueprint assignable delegate that fires when the possessed pawn changes. This should fire in both singleplayer and networked games. The bug is reproducible in single play ...