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/ ...

heterogeneous volumes SkyLight VolScatter Intensity not working

UE - Niagara - Rendering - Jul 23, 2025

Heterogeneous Volumes do not respect the Volumetric Scattering Intensity values when running with Lumen, but do (correctly) when rendering with the Path Tracer. ...

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

UE - Rendering Architecture - Materials - 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 ...

When exporting a level sequence (with its associated level) to USD, the asset paths for the reference are different from 5.5 and older

UE - Editor - Content Pipeline - USD - Jul 21, 2025

In 5.6, a referenced asset path looks something like         prepend references = @../../../../../Data/USD/Exports/FN-Main/ExportFolder/Assets/Sphere.usda@ instead of         prepend references = ...

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 ...

Regression with RecomputeTangents on SkeletalMeshes in 5.6

UE - Graphics Features - Jul 21, 2025

Licensee noticed a regression in 5.6 where the non-masked recompute tangents option doesn't work anymore. The option is called "Enabled with no mask" in 5.6 but "All" in 5.5. Under the hood, this se ...

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 - World Creation - Worldbuilding Tools - 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 ...

Crash when travelling during ability activation when URL contains "#"

UE - Framework - Jul 18, 2025

This issue is related to [Link Removed], where the "?listen" option sent on the URL to clients could cause issues with RPCs being called locally during travel. The fix to remove the "?listen" option ...

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 ...