Unreal Engine Issues
Unreal Engine Issues
ULevelSequence trying to duplicate a REINST_ class when creating new custom binding in ConvertOldSpawnables()
UE - Framework - Blueprint Compiler - Jul 23, 2025The assert that we're hitting is:Cannot replace existing object of a different class. New Object: /Engine/Transient.REINST_BPC_NPC_VFX_C_230 /Game/Maps/[REDACTED]/Levels/[REDACTED]/LevelSequence/ ...
Farfield shadow in lumen scene
UE - Graphics Features - Jul 21, 2025Shadows in the Lumen Scene from Lumen's Direct Lighting do not match the world when in the Lumen Far Field. This leads to shadows where there should not be any, and missing shadows where there shou ...
Montage Editor: Mouse Wheel Cannot Scroll to the Bottom of notify section when there are many track.
UE - Anim - Runtime - Jul 21, 2025When a large number of notify tracks are added in the Montage Editor, the mouse wheel scroll does not allow the user to reach the bottom-most tracks. Only by manually dragging the scrollbar can the ...
UMaterialFunctionInterface not being tagged as BlueprintType makes some editor scripting scenarios difficult
UE - Rendering Architecture - Materials - Jul 21, 2025UMaterialInterface is BlueprintType, but UMaterialFunctionInterface is not. This makes it difficult to port some BP logic that works with materials to the material layer system. Crystal Dynamics wou ...
Performance slowdown when ray tracing is disabled due to SetResidencyPriority
UE - Rendering Architecture - RHI - Jul 17, 2025When a game is compiled with ray tracing disabled (D3D12_RHI_RAYTRACING=0) and the GPU the game is running on becomes low on VRAM, frame time is negatively impacted and doesn't recover. The D3D12_RH ...
Niagara Regression - Looping particle with Spawn Burst Instantaneous on time 0.0 flickers for a frame between loops
UE - Niagara - Jul 16, 2025Note: This worked correctly up to UE 5.4, but repros from UE 5.5 up to mainline latest. If a Niagara Emitter is set up with "Spawn Burst Instantaneous" on time 0.0, and the spawned particle(s) have ...
Bake Pose is not applied correctly when using LODSettings asset
UE - Anim - Rigging - Jul 16, 2025The Bake Pose setting does not work when using a SkeletalMesh LODSettings asset. After the change in CL22878911, the BasePose in the LODSettings asset is no longer copied to the BakePose in the skel ...
Drag-and-drop any cooked Blueprint class asset into the level viewport crashes the editor
UE - Framework - Blueprint - Jul 14, 2025Dragging any cooked Actor-based Blueprint class asset into the level editor viewport will crash the editor when it has been configured to work with cooked assets. This is a regression that started ...
Interchange framework is bypassed on the second attempt after a failed import
UE - Editor - Content Pipeline - Import and Export - Jul 14, 2025Hello! We have encountered a bug with the Interchange pipeline. When an interchange texture import is cancelled due to non-power of 2, and then the same texture is imported again without any change ...
When moving actors to the current level, their label is reset and displayed incorrectly on the Scene Outliner until the next time it is refreshed
UE - Editor - Workflow Systems - Jul 14, 2025This is a regression, it worked correctly up to UE 5.4, but repros on UE 5.5 and 5.6. Also, this seems related to [Link Removed], which was fixed by CL 40649716/40649749 and integrated into UE 5.6, ...