LODs with screen size 0 in legacy assets are incorrectly converted to 1 on load

UE - Editor - Content Pipeline - Sep 11, 2025

When loading a mesh asset (static or skeletal) created in an old version of Unreal (e.g. 4.10), any LOD whose LOD screen size was originally set to 0, is converted to 1. This causes LODs that would ...

Downsampled SceneColour textures are not invalidated after ComposeToNewSceneColor when TSR is enabled leading to AfterMotionBlur materials not rendering bloom

UE - Graphics Features - Sep 11, 2025

When an emissive AfterMotionBlur material is used with TSR, Bloom is not applied to the material. The cause for this appears to be that AfterMotionBlur materials are composed to a separate texture ...

SkyLight Leaking does not affect reflections when the SkyLight is static but static lighting is disallowed

UE - Graphics Features - Sep 10, 2025

Reflections do not receive SkyLight leakage contribution from a static SkyLight when static lighting is disallowed. This is caused by the function UpdateSkyIrradianceGpuBuffer checking if the SkyLig ...

[AI] Failed check in UMassSpawnerSubsystem::DestroyEntities due to EntityManager still procesing

UE - AI - Mass - Sep 7, 2025

It crashed when unspawning an AI which will destroy its entity. Inside DestroyEntities "IsProcessing" is true, but when it breaks into the debugger, "ProcessingScopeCount" is 0 (so IsProcessing shou ...

Crash when changing r.MaterialQualityLevel when FastGeo plugin enabled in cooked build

UE - World Creation - Worldbuilding Tools - Sep 5, 2025

The engine crashes when the r.MaterialQualityLevel is changed in a cooked game that uses the FastGeo Streaming Plugin. The crash doesn't repro with the same steps in Editor, just in a cooked build. ...

Crash when opening a texture or editing its properties after stopping a preview in the material editor

UE - Rendering Architecture - Materials - Sep 5, 2025

When a texture asset has certain properties edited, its PostEditChangeProperty() method calls to UTexture::NotifyMaterials(), which triggers a recompilation of materials that reference it in their m ...

DirectoriesToAlwaysCook in platform specific configuration files are ignored by the cook process

UE - Platform - Console - Sep 5, 2025

When DirectoriesToAlwaysCook is placed in a platform-specific configuration file, the cook process does not read that entry when cooking content for that platform. The editor is aware of the platfo ...

MRQ - Subgraphs do not evaluate properly in Quick Render

UE - Virtual Production - Tools - MRQ - Sep 4, 2025

Subgraphs do not seem to be evaluating properly with Quick Render. Message from the EPS: "While testing out Quick Render, I've found that subgraph nodes are not being evaluated. Digging into it dee ...

Invalid GUIDs on new material instance parameters cause overrides to break on base param rename

UE - Rendering Architecture - Materials - Sep 3, 2025

When a parameter value is assigned on a newly created material instance (constant or dynamic) using Set***ParameterValueInternal, the parameter’s ExpressionGUID is left invalid (0,0,0,0). Parameter ...