ChaosWheeledVehicleMovementComponent is breaking the const CDO contract and changes to the instances are being applied to the CDO

UE - Simulation - Gameplay - Apr 28, 2025

As described by the licensee, the const CDO contract is being broken on ChaosWheeledVehicleMovementComponent. The issue the licensee is facing is that by spawning cars with different configurations, ...

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 - Simulation - Core - 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

UE - Editor - Developer Usability - Jun 20, 2025

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 ...

In a Geometry Collection, enabling Nanite Fallback in a Nanite Enabled collection won't generate a Physics Body when Nanite is disabled

UE - Simulation - Visual - Jun 30, 2025

In a Geometry Collection, enabling Nanite Fallback in a Nanite Enabled collection won't generate a Physics Body when Nanite is disabled. To verify this, follow the steps provided in the Steps to Re ...

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 ...