Crash when displaying lumencards on map with many objects

UE - Rendering - 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 ...

Windowed game window can restore to the wrong size due to DPI Awareness is configured after setting initial window size

UE - Graphics Features - Jul 31, 2025

If in use, DPI Awareness is set after the initial window size is set. For a Windowed window, the settings are unable to restore the prior resolution settings on an application restart due to the pr ...

Unloading a World Partition region during nested Level Instance inline editing prevents exiting editing mode

UE - World Creation - Worldbuilding Tools - Level Instances - Jul 28, 2025

In the case of a single-layer Level Instance, actors are still referenced even when the region is unloaded. However, in the case of nested Level Instances, the level being edited is discarded when t ...

Mutable RemoveMesh node with data from DataTable

UE - Anim - Mutable - Jul 28, 2025

Hi, We are trying to use Mutable plugin to avoid clipping using the RemoveMeshNode with data from DataTables. However we are having trouble with the most basic example of our idea. We have a Data ...

Artifacts appear on translucent particle systems during camera motion blur

UE - Rendering - Architecture - Jul 23, 2025

Translucent particle systems exhibit visual artifacts when the camera moves, even though motion vectors are disabled for the particle emitters. While switching the Translucency Pass to "After Motio ...

Farfield shadow in lumen scene

UE - Rendering - Graphics Features - Jul 21, 2025

Shadows 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, 2025

When 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 ...

Performance slowdown when ray tracing is disabled due to SetResidencyPriority

UE - Rendering - Architecture - RHI - Jul 17, 2025

When 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, 2025

Note: 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, 2025

The 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 ...