Unreal Engine Issues

Race condition in GetFunctionSig_Write() and other function signatures

A race condition exists in GetFunctionSig_Write() and other places where FNiagaraFunctionSignature  is lazily initialized because multiple worker threads can progress past if (!Sig.IsValid()) and st ...

LevelInstance\PackedLevelActor: Problem with non-uniform negative scale.

A licensee is reporting transform issues related to using non-uniform negative scale on LevelInstances and PackedLevelActors. ...

Crash when a floor mesh is removed while a Vehicle has SimulatePhysics disabled

When SimulatePhysics is disabled, the constraint update is skipped, so a reference to an invalid (already-removed) particle is left behind. As a workaround, the approach suggested by the licensee — ...

Level Sequence spending long time validating assets

Hi After migrating our animation project from 5.7 -> 5.8 we notice that some level seqeunces take much longer to save (during validation stage). This issue only exhibits when using control rigs in ...

Sequencer Crash (GC Leak) in Editor

A GC leak, similar to the one fixed by 44483919 but for Level Sequences in Level Instances rather than ones with Widgets. A Level Sequence Actor in a Level Instance points to a Level Sequence Asset ...

[Mutable] Morph Targets can be disabled in packaged builds when Mesh Streaming is enabled

When a Mutable mesh instance is created while the actor spawns at a distance, only the low LODs are generated, and the mesh is created with no Morph Targets registered. Later, when the camera approa ...

Editor crash when an unsupported material domain or blend mode is selected when previewing a Nanite mesh in the material editor

Fix in UE6: 56133257 This Jira is for 5.8.3 tracking ...

All UKismetStringTableLibrary public method visibility unexpectedly changed from public to private.

Cannot get Texture Size property from Texture Collections

The following error is shown when attempting to use the Texture Size of a Texture Collection texture object: Texture size only available for Texture2D, TextureVirtual, Texture2DArray, VolumeTexture ...

MRG - Cinematic Assembly Tokens From Metadata Return Empty When Rendering

Metadata defined on a Cinematic Assembly isn’t accessible as naming tokens when rendering with Movie Render Graph. Global naming tokens defined outside of a Cinematic Assembly does work but context ...