Editor crash when building lighting and world partition minimap

UE - World Creation - Worldbuilding Tools - World Partition - Apr 17, 2025

It is possible for an editor crash to occur if a build is running (Lightmass in this case) and another is launched such as Build World Partition Minimap (as well as HLOD and Spline builders). This i ...

Bug: Level Sequence OriginOverrideLocation not propagating to newly added nested ShotTracks

UE - Anim - Sequencer - May 14, 2025

Within a Level Sequence, it's possible to override the transform (OriginOverrideLocation) of a ShotTrack. This generally works as expected — all nested ShotTracks should inherit and apply the transf ...

VSM SMRT SamplesPerRay CVars behave differently if groom assets are present leading to a potential full-scene shadow

UE - Graphics Features - May 28, 2025

When a groom is present, setting any SamplesPerRay SMRT CVar to zero results in an unexpected complete shadow projected from the light. ProjectLight() in VirtualShadowMapProjection.usf has addition ...

Plugin dependencies causing RI parameter initialization failures (UDN)

UE - Niagara - Oct 6, 2023

Error on some Niagara emitters using the WindForce module: LogNiagaraEditor: Error: Invalid input type found while attempting initialize new rapid iteration parameters. Function Node: /Game/FX/Expl ...

EditCondition tag not working for FInstancedStruct property in UDeveloperSettings

UE - Editor - Workflow Systems - May 30, 2025

When using EditCondition to control the editability of FInstancedStruct properties in a class derived from UDeveloperSettings, the condition is only partially respected. Specifically: A TArray<FIns ...

Editor mode keyboard shortcuts active when in Play In Editor

Editor mode keyboard shortcuts active when in Play In Editor. This behavior is a departure from previous versions. It was described by the licensee as confusing and it clashes with gameplay assigne ...

TInstancedStruct used in native actor class loses reference to Instanced UObject after BP recompilation

UE - Framework - Blueprint Compiler - Jun 25, 2025

When a TInstancedStruct contains a UObject marked with EditInlineNew and DefaultToInstanced, the reference is lost after compiling the Blueprint but only when the struct is part of a native Actor cl ...

Conflict between sequencer transform track and Parent Constraint from the Animation Mode breaks temporary pivot translation on any actor

UE - Anim - Anim in Engine - Jul 15, 2025

Note: This affects all versions from at least UE 5.3, including mainline latest. The "Animation" Editor Mode allows creating constraints for level actors. One of these, the "Parent" constraint, con ...

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 = ...