ULevelSequence trying to duplicate a REINST_ class when creating new custom binding in ConvertOldSpawnables()

UE - Framework - Blueprint Compiler - Jul 23, 2025

The 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/ ...

Custom Primitive Data color widget not applying correctly to static mesh components in Blueprint editor.

UE - Framework - Blueprint Editor - Jul 23, 2025

Context Custom Primitive Data is used to store custom data in an index array that is accessible through Blueprint and code. This allows for variations across instances of the same mesh without needi ...

Farfield shadow in lumen scene

UE - 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 ...

Cascade Shadow Map octree not handling new max world size

UE - Graphics Features - Jul 21, 2025

Cascaded Shadow Maps do not use the proper world size for octree culling. At far distances, the shadows are always culled. ...

UE5.6+ - Mutable - IDPrefix crash when combining Child Objects, Add to Mesh Component and Extend Mesh Section.

UE - Anim - Mutable - Jul 21, 2025

So the issue seems to be a combination of Add To Mesh Component and Extend Mesh Section. I've tried this in Epic Launcher 5.6, 5.6 in-house modified engine as well as ue5-main 5.7 from git (editor ...

UMaterialFunctionInterface not being tagged as BlueprintType makes some editor scripting scenarios difficult

UE - Rendering Architecture - Materials - Jul 21, 2025

UMaterialInterface 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 ...

Unable to change Actor Coloration View Modes in PIE

UE - Graphics Features - Jul 20, 2025

When in PIE changing Actor Coloration view modes from the viewport visualisation mode [Liit] -> [Actor Coloration] -> ... Does not update correctly when switching view mode and sometimes isn't corr ...

Structured log automated decimal number tests fail in languages / cultures that use commas instead of periods

UE - Foundation - Jul 17, 2025

The following Localisation Tests in "Engine\Source\Runtime\Core\Tests\Logging\StructuredLogFormatTest.cpp:275" TestLoc(LOCTEXT("Float", " {Float} "), ANSITEXTVIEW(R"(128.25)")); TestLoc(LOCTEXT ...

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 ...